C++ For Beginners

Check given String for Palindrome

2017-08-22T13:55:00.003-07:00

Program: Find given string is palindrome or not

Palindrome: A palindrome is a word, phrase, number, or other sequence of characters which reads the same backward as forward, such as madam or racecar.

So in this program we take input string from user and return the result whether its palindrome or not.

#include <iostream>
using namespace std;

int main() {
char str[100]; // declare char variable of length 100 i.e. max 100 character string can be taken input
cin >> str; //take input
int strLength = 0; //initialize the length of string to zero
bool palindrome = true; //let assume given string is palindrome
for(int i=0;str[i]!='\0';i++,strLength++);
/*
to understand above statement first remember array of char ends with '\0'. '\0' represents null character. So we can determine the end of string '\0' to calculate the length of string. So here we first initialize the length by 0 then we begin the loop from i =0 and we check character at i^th position for null character '\0', so we are increment string length with the value of i. So when we encounter '\0' it means end of string so length is calculate with the value of i.
*/
for(int i=strLength-1,j=0;j<(strLength/2)+1;i--,j++){
if(str[i] != str[j]){
palindrome = false;
break;
}
}
/*
Now to check palindrome we check starting half of string should be match with half from end. For even length it will divide perfect in two parts whereas for odd it will left with one character that we don't need to check as its in middle and common.
Now we declare two counter first denote the position of start of string and other end of string[Remember index start from 0 so here strLength is total length so last Index will be strLength -1 ]. So we run the loop upto half length of string length and we increment j(start counter) and decrement i(end counter).
In each loop pass we check character of ith position and jth position to be same. If they mismatch in any one of the case then we can says given string is not a palindrome. So by default we assume its palindrome if condition doesn't match mean its palindrome.
*/
if(palindrome){ //print the output
cout << "Given String is Palindrome";
}
else{
cout << "Given String is not a Palindrome";
}
return 0;
}

Program: Print first 10 Perfect Number

2016-12-05T10:47:00.001-08:00

Program: Find or Print first 10 Perfect Number

Perfect number is a positive number which sum of all positive divisors excluding that number.
For example: 6 is perfect number as divisor of 6 are 1, 2, 3. Sum of it divisor is 1 + 2 + 3 = 6.

Simple way to do is find divisor of each element and check for perfect number. But it is slow as it take more time.
So there is general way to find perfect number as given in wikipedia, perfect number exist only for even number. It is given by 2^p−1(2^p − 1) where p is a prime number
For example for p = 2 : 2¹(2² − 1) = 6,
similarly for p = 3 : 2²(2³ − 1) = 28 ...

So in this program we are printing up to 10 perfect number.

#include <iostream>
#include <cmath> //for pow function
using namespace std;

bool isPrime(int n) //check prime number
{
//this snippet is taken from program: Check given number for Prime Number
bool flag = true;
if(n<2)
flag = false;
else if(n == 2)
flag = true;

else if(n%2 ==0)
flag = false;
else{
for(int i=3;i<n;i+=2){
if(n%i == 0)
{
flag = false;
break;
}
}

}
return flag; //return boolean value
}

/*
using above formula we made function which return the perfect number according to given prime number.
*/
unsigned long long getPerfectNumber(int n){
return (pow(2,n-1)*(pow(2,n)-1));
}

int main()
{
//print for prime number = 2
cout << getPerfectNumber(2)<<endl;
for(int i =3,j=1;j<10;i+=2){
if(isPrime(i)){ //check prime if found then will print perfect number
cout << getPerfectNumber(i)<<endl;
j++;
}
}
return 0; //https://cplspls.blogspot.com

}

OUTPUT:

For those who want to do by simple way by check each number for perfect number then here is program:-

#include <iostream>
using namespace std;

int main() {
unsigned long long sum;
int n = 4; //number of perfect number to print
for(int i=2,j=0;j<n;i++){//we start from 2 and start checking each number
sum = 0;
for(int j=1;j<i;j++){ //find divisor
if(i%j == 0)
sum+=j; //add divisor
}
if(sum == i){ //compare sum with number
cout << sum<<endl;
j++;
}
}
return 0;
}

Above program sure look small as compare to above one but time taken to print 10 elements will take a lot of time and memory while first code will give answer within few seconds.

Program: Print first n Prime Number

2016-12-01T00:30:00.000-08:00

Program: Print first n Prime Number

We earlier done the program of how to check Prime Number, in that program we are checking whether the given number is prime or not.

In this program we are taking input n and printing first n prime number.

Prime number is a number which is greater than one and can only divide by 1 or by its own number.

#include <iostream>
using namespace std;

//we already discuss about how to check prime number so we create a function
bool isPrime(int n)
{
//this snippet is taken from program: Check given number for Prime Number
bool flag = true;
if(n<2)
flag = false;
else if(n == 2)
flag = true;

else if(n%2 ==0)
flag = false;
else{
for(int i=3;i<n;i+=2){
if(n%i == 0)
{
flag = false;
break;
}
}

}
return flag; //return boolean value
}

int main()
{
int n,i;
cout << "Enter value of n : ";
cin >> n; //input n
if(n>1)
{
cout << "2 ";
n--;
}
/*
we print first prime number i.e. 2 earlier to increase the speed of program as i discussed earlier in my last program that 2 is only even prime number. Rest of prime number are odd. So we have to print 2 earlier to run loop with increment of two. This way it checks less number of number and increase its speed.
Now loop run till n value drop to zero that each value we print will decrement value of n. So we can print exactly n number only.
In loop we pick number and check whether it is prime or not from function which return true or false. According to result we print the prime number or not.
*/
for(i=2;n>0;i+=2)
{
if(isPrime(i))
{
cout << i << " ";
n--;
}
}
return 0; // https://cplspls.blogspot.com
}

OUTPUT:

Introduction to User Defined Functions

2016-11-30T12:04:00.000-08:00

Introduction to User Defined Functions

A function is a group of statements that together perform a task. Every C++ program has at least one function, which is main(), and all the most trivial programs can define additional functions.

We have study about #define in previous lessons. Functions is similar to #define but less secure than functions as it doesn't have any return type or data type of parameters which provide certain level of data security.

Functions usually defined because a certain snippet of code are used again and again. So instead of writing again and again we create a Function which stores the required statement to execute and it may return result according to return type.

Functions are used to provide modularity to a program. Creating an application using function makes it easier to understand, edit, check errors etc.

A function is also known as method or a sub-routine or procedure etc.

Syntax of Function

return-type function-name (parameters){
// function-body
}

A C++ function definition consists of a function header and a function body. Here are all the parts of a function:

Return-Type: The return-type is the data type of the value the function returns. return-type can be of any data type or user defined type also. It can be void when we don't have to return anything.

Function Name: The function-name is name of function through which we gonna call it.

Parameters: A parameter is like a placeholder. When a function is invoked, you pass a value to the parameter. This value is referred to as actual parameter or argument. The parameter list refers to the type, order, and number of the parameters of a function. Parameters are optional; that is, a function may contain no parameters. Parameters are also known as Function Signature.

Function Body: The function body contains a collection of statements that define what the function does.

Function Declaration includes

return-type function-name (parameters);

Function declaration is similar to function defination just without function body.

In C++ before calling function we must either define the function or declare the function. If we try to call function from main() and it is defined after the main() method then it will give compile error as compiler doesn't recognize the function as its not defined till now. So we need to tell compiler by declaring earlier or define the function.

Below example contain usage of both defining and declaring the function before main method.

Example:

#include<iostream>
using namespace std;

void display(int x); //declaring the function
//define the function
int calculate(int x,int y) //int = data type
//calculate = function-name
//int x, int y = function parameter or signature
{
return x+y; //return integer type
}
int main()
{
int x = calculate(2,5);
display(x);
return 0; // https://cplspls.blogspot.com
}
void display(int x) //definition of function which is declared above
{
cout << x<<endl;
}

OUTPUT:

Program: Check given number for Prime Number

2016-11-30T02:59:00.000-08:00

Program: Check given number for Prime Number

We know about prime number is a number which is greater than one and can only divide by 1 or by its own number. In this program we check the given number for prime number.

#include <iostream>

using namespace std;

int main() {

int n;

cout << "Enter Prime Number: ";

cin >> n; //input number

//initialize flag for true assume given number is prime number

bool flag = true;

//if number is less than 2 than its not a prime number according to def

if(n<2)

flag = false;

else if(n == 2) // if n is 2 than its prime number

flag = true;

else if(n%2 ==0)

flag = false;

else{

Now we check n > 2 whether its prime or not. We check for 2 earlier because from now on we are gonna skip all even number as other than 2 there are no even prime number as all divisible by 2. So we start with 3 and check up to n with increment of two in one loop. So if any number less than n found divisible with n then set flag to false and break the loop.

for(int i=3;i<n;i+=2){

if(n%i == 0)

{

flag = false;

break;

}

//print output according to flag value

if(flag)

cout<<"It is a Prime Number";

else

cout<<"It is Not a Prime Number";

return 0; //https://cplspls.blogspot.com

}

OUTPUT:

Use of goto Statement

2015-12-12T08:10:00.002-08:00

Using goto Statement

goto statement is used to jump on a particular location in a program defined by label. Label is a name given to a location.
Label is defined by a <locationName> followed by a colon.
goto is use with goto <labelName>;

syntax of label & goto

statment 1;
label: //syntax of label
statment 2;
statment 3;
if(statement) //if condition true
{
goto label;
//jump to label i.e. after statement 1 and program will execute again statement 2 and 3
}

Let Check out Example for better understanding

Ex1: Print first 10 Natural Number
#include<iostream.h>
int main()
{
int i=1;
print:
cout << i <<endl;
if(i<10)
{
i++;
goto print; //jump to print label as define above after initialization of i
}
/*
In Above Program we are printing first 10 natural number using goto statment
in this example goto is used as loop to print 1 to 10
first we initialize the variable i to 1
then we define a checkpoint or label for using with goto
then we print value of variable i
we check if variable i is less than 10 if true then increment of variable i and jump to checkpoint or label we define earlier to print again this process continue till condition is false similar in a loop
*/
return 0;
}

OUTPUT

Ex2: Divide Two Numbers [check this program using loop]
#include<iostream.h>
int main()
{
//Divide Two Numbers
char ch;
float a,b;
tryAgain:
cout << "Enter First Number : ";
cin >> a; //Input First Number
cout << "Enter Second Number : ";
cin >> b; //Input Second Number
if(b == 0) // Check for divisor for zero
{
cout << "Error: Number Cannot Divide by Zero"<<endl; //return error message
goto tryAgain;
}
cout << "Answer = " << a/b<<endl;

cout << "Try Again(y/n): ";
if(cin >> ch && ch != 'n')
goto tryAgain;

/*
In this example we are dividing two number and check for divisor not equal to zero
first we define label before taking input from user
then we take input two numbers
if (divisor(here b) = 0) then print error message and goto label; that jump back to a point where we have to take input again
now if divisor is not zero then we print answer and ask user for more
here you can see expression in if condition
if(cin>> ch && ch != 'n')
above if statement has two conditions for check as there is AND(&&) between them means both must be true
check each conditions cin >> ch this will return true when it take input successfully
and then it compare ch != 'n'
means here we are do two operation that first we take input and check for equality in one statement
second condition will run only when we get input from first statement
so if its true then it goto label;
else <end of program>
*/
return 0;
}

Output

Use of Continue Statement

2015-12-11T12:48:00.000-08:00

Using Continue Statement

Continue statement is used to skip the current iteration and force to execute next iteration by skipping any code after continue statement inside a loop.
In simple term whenever you encounter continue statement in a loop it will skip the current pass execute next pass and also it skip the other statement below the continue statement inside a loop.

Let check the following examples for better understanding:

Ex1: Print Odd Number
#include<iostream.h>
int main()
{
//Print odd number
for(int i=1; i<=10;i++)
{
if(i%2==0)
continue;
/*
Above two lines first line check if i is even or not, If its even then i%2 return zero
means condition is true for even number of i then continue statement will execute.
As you can see in output we are printing only odd numbers so whenever continue statement runs it will skip all next line inside a loop and go to next iteration that increment of i
*/
cout << i<<endl;
}
return 0;
}

OUTPUT

Ex2: Divide Two Numbers
#include<iostream.h>
int main()
{
//Divide Two Numbers
char ch;
float a,b;
do //Using Do While Loop
{
cout << "Enter First Number : ";
cin >> a; //Input First Number

cout << "Enter Second Number : ";
cin >> b; //Input Second Number

if(b == 0) // Check for divisor for zero

{

cout << "Error: Number Cannot Divide by Zero"<<endl; //return error message

continue;

In this whenever we encounter with divisor = 0 then error message is display

and continue statement will execute. Whenever Continue statement runs it will skip all the code after that inside a loop and start from next iteration. As in this example we are using Do while loop which check condition at the end but we already skip the statements after continue so we will don't check the condition and we will start loop from begin. As you can seen in Output

}

cout << "Answer = " << a/b<<endl;

cout << "Try Again(y/n): ";

cin >> ch;

}while(ch != 'n');

return 0;

}

Output

Program: Display Fibonacci Series IN C++

2013-10-05T01:05:00.001-07:00

Program : DISPLAY FIBONACCI SERIES IN C++

Check out Program

#include<iostream.h>
#include<conio.h>
// Display Fibonacci Series
// In Fibonacci Series first two numbers in the Fibonacci series are 0 and 1, and each subsequent number is the sum of the previous two.
int main()
{
int a=0,b=1, c,n;
cout << "Enter the value of n ";
cin >> n; // n store the integer value that series will shown upto n terms
cout << endl << a <<" " <<b << " " ;
for(int i =0; i<(n-2); i++)
{
c = a+ b;
cout << c << " ";
a=b;
b=c;
}
/* First we Print first Two Term of Series then using for loop we generate rest of series upto n term. Let Begin with loop first it begin from 0 till the n-2 term because we already print first two term of series, then inside loop we initialize c = a + b, c contain value sum of a + b which become the third term of series. In Fibonacci series sum of previous two term is the next term. After getting value of next term and store in variable c. Then swapping of variable take place, now we don't require first term for next term(i.e. 4th term) so we replace value of a with b and replace value of b with c. Now 1st contain 2nd and 2nd contain 3rd, so they can generate 4th and so on. This process going on until the nth term of series. It will Print output after every assigning value of c.
*/
getch(); //http://cplspls.blogspot.com
return 0;
}

OUTPUT:

Above Program Without Comments
#include<iostream.h>
#include<conio.h>
int main()
{
int a=0,b=1, c,n;
cout << "Enter the value of n ";
cin >> n;
cout << endl << a <<" " <<b << " " ;
for(int i =0; i<(n-2); i++)
{
c = a+ b;
cout << c << " ";
a=b;
b=c;
}
getch(); //http://cplspls.blogspot.com
return 0;
}

Program: Find Factorial of a Given Number

2013-10-04T04:10:00.001-07:00

Program : FIND FACTORIAL OF A GIVEN NUMBER

Program to find factorial of a number using For Loop
Check out Program

#include<iostream.h>
#include<conio.h>
// Find factorial of a Given Number
int main()
{
long double factorial = 1; /* factorial has long double type which take 8 bytes in memory and it can store number within range of 1.7E -308 to 1.7E + 308 */
int n;
cout <<"Enter a Number : "<<endl; // endl for new line
cin >> n; // Take Integer value from user and store in variable n

for(int i =n; i>0; i--)
factorial *= i;
/* You Know Factorial is product of all positive number integers less than or equal to n. In above loop we initialize i equal to value of n that is taken from user, then set condition that i > 0 because we do multiplication here if i = 0 then it will give result 0. Then in loop statement is factorial * = i , it means that factorial = factorial * i , Now we already assign factorial value as 1, if we don't assign value 1 it will give error or junk value, because we are doing multiply if there is no number to multiply with it give junk value. In this we use decrement of value of i from n to 1, so it will multiply number like this n * (n-1) * (n-2) * ... * 2 * 1 . In this loop i didn't put braces because any loop or condition if you didn't put braces then it will automatic consider next line or till the termination(;) it will consider that part inside loop. So next line to loop inside the loop after that loop scope is finished.
*/
cout << n << "! = " << factorial <<endl;
getch(); //http://cplspls.blogspot.com
return 0;
}

OUTPUT:

Above Program Without Comments
#include<iostream.h>
#include<conio.h>
int main()
{
long double factorial = 1;
int n;
cout <<"Enter a Number : "<<endl;
cin >> n;

for(int i =n; i>0; i--)
factorial *= i;

cout << n << "! = " << factorial <<endl;
getch();
return 0;
}

Program : Equilateral Triangle empty from inside

2012-01-28T22:07:00.000-08:00

Program : Equilateral Triangle empty from inside

Program to create a triangle like only triangle outline
Check out Program

#include<iostream.h>
#include<conio.h>
// Create an Equilateral Triangle empty from inside
int main()
{
    int i=0,sp; // int define i and sp
for(i=0; i<=10; i++) // first loop that work for 11 times
    {
    for(int sp=0; sp<=10-i; sp++) // loop for space like first time 5 then 4 then 3 and so on
       {
           cout << " ";
       }

        for(int j=0; j<1; j++) // loop to print xx that work only one time
        {
        cout <<"x";
        for(int m=0; m<=2*i; m++) // inside this one loop for give space b/w two x
{     cout<<" ";}
        cout <<"x";
        }
        cout <<endl; //next line
    }

    for(int s=0; s<=i; s++) //print last line with xx
    cout << "xx";
    cout <<endl;
    getch(); //http://cplspls.blogspot.com
    return 0;
}

OUTPUT:

Using Switch & break Statement

2012-01-11T04:06:00.000-08:00

Using Switch & Break Statement

Switch statement is used instead of if statement using if statement multiple time can replace with switch and this make program short.
Break statement is used break that code proceed next like for loop i set to run 5 time and i write break it only run 1 time it skip braces part and continue to rest of code. Its used in loops and switch...

syntax of switch:
switch(variable)
{case 1 : statement
break;
case 2 : statement
break;
case 3 : statement
break;
...
...
default : statement
break;
}

Check the example:

#include<iostream.h>
#include<conio.h>
int main()
{char a;

//check the user input is vowel or not

cout << "Enter any character \n";
cin >>a;
switch(a) //no semi colon
{
case 'a':
case 'e':

case 'i':

case 'o':

case 'u':
case 'A':
case 'E':

case 'I':

case 'O':

case 'U': cout<<"Your input is Vowel\n";
break;

default : cout << "Your input is not vowel\n";
break;
}

above i take input from user and under switch braces i write that variable here choice is made and it switch to according to that Case

like here if i enter a character then it goto switch(a) then it redirect to selected case like case 'a' then it print

'Your input is Vowel'

if you enter anything z then it redirect to default that display

'Your input is not vowel'

and break statement is necessary to differentiate cases that if you didn't write break then it execute all other cases after that like if i enter a then it also print your input is not vowel if i didn't set break

thats why i write only one time

'Your input is Vowel'

and no break between them and in end i set break!!!

*/
getch();
return 0;
}

OUTPUT

Program: To check given character is Alphabet, Digit or any Other

2012-01-07T23:47:00.000-08:00

Program: To check given character is Alphabet, Digit or any Other

#include<iostream.h>
#include<conio.h>
//check given character is alphabets, digit or any other character

int main()
{
   char a;
   cout <<"Enter a character : \n";
   cin >> a;
   if(((a >= 'A') && (a<='Z')) || ((a >='a') && (a <= 'z')))
   cout << "You entered an Alphabet\n";
   else if(a >= '0' && a <='9')
   cout << "You entered a digit\n";
   else
   cout << "You entered non alpha numeric character\n";

   /* i define char a that contain only one character and then i take input
   from user. and then i set condition to check what type of data user enter
   first condition that i set a >= 'A' && a<='Z' and in these i write two condition]
   joining with && now understand the function of && this is used to check that both the condition is
   true or false like here i set a>= 'A' && a<='Z' this condition run when both is true
   this condition mean that value is between A & Z and now see full condition
   that condition i for uppercase now check for lower case we separate condition
   with OR sign '||' this mean condition must true either one of the side must true
   like here (((a >= 'A') && (a<='Z')) || ((a >='a') && (a <= 'z')))
   first uppercase check if it false then it check lower case either one of these
   true then only it execute then it print you enter alphabet

   Now second condition you can see to check number (a >= '0' && a <='9')
   i use else if condition u can also use if condition under else
   like else
   {
       if((a >= '0' && a <='9')
       cout<<"You enter Number";
   }

   like this you can also give its same the above condition check the number
   between 0 to 9

   and third is else part other than above number or alphabet it execute
   that part
   */
   getch();
   return 0;
}

OUTPUT

Program : To Accept 5 Integer and Print Larger one

2012-01-07T07:41:00.000-08:00

Program : To Accept 5 Integer and Print Larger one using if statement

In this program i use if statement to check the largest no.
check the program:

#include<iostream.h>
#include<conio.h>
//Accept 5 Integer and Print Larger one
int main()
{
int a,b,c,d,e,f;
cout << "Enter Five Number\n";
cin >> a >> b >> c >> d >>e; //it take 5 no one after one
//let f is maximum no. & set that no. to be a variable
f =a;
//we assume a is max and then we set the condition with if
// statement and it will swap f value to largest one let chek it out
if(b>f)
f =b;
if(c>f)
f=c;
if(d>f)
f=d;
if(e>f)
f=e;
/*
In this i set 4 condition and u see every condition give i didnt give any braces
because when we write without braces then it autoatc consider its scope
that next line to that condition only
like in every four condition aboce the scope of
assigning value is till there only one line

and above condition replace no according to condition true
that no greater than f
Its simple using if statement
*/
cout << "Largest No is " << f;

getch();
return 0;
}

OUTPUT

Program : Create Equilateral triangle

2012-01-07T07:06:00.000-08:00

Program : Create Equilateral triangle

To make an Equilateral triangle we need total three loop two loop inside one loop. It will print Equilateral Triangle using word xx
Check Out Program for Better Understand.

#include<iostream.h>
#include<conio.h>
// Create an Equilateral Triangle
int main()
{
for(int i=1; i<=8; i++)
    {
        for(int sp=1; sp<=8-i; sp++)
        {
            cout << " ";
        }

        for(int j=1; j<=i; j++)
        {
        cout <<"xx";
        }

        cout <<endl;
    }
/* Loop set to int i = 1 and less than or equal to 8 this means this
loop run 8 times under every time two more loop runs one that loop
give space like i wanna make xx equilateral triable like that
____xx____
___xxxx___
__xxxxxx__
_xxxxxxxx_
like this _ is space, we need to give this space i use 2nd loop
and this loop help to give spaces that here
i give first 7 space than next line 6 next 5 and so on
i set sp value to 1 and sp <=8-i initially i =1 and this imply sp value
is less than or equal to 7 at begin and this give 7 spaces and then
Now 7 spaces is given
then it proceed to next loop that is to print the xx
initally value of j =1 and its less than or equal to i and
initially i =1 and the condition is true then its run and print
xx one time
and then it give new line
and then i increment is done and same procedure done again
now in space loop it give 6 spaces
and then print xx two times
and then next line
and this procedure go on...
*/
    getch();
    return 0;
}

OUTPUT

Program :Make Alphabet Triangle

2012-01-05T08:11:00.000-08:00

Program :Make Alphabet Triangle
In This Program I use Nested Loop To Make a Alphabet Triangle check out Program.

#include<iostream.h>
#include<conio.h>
int main()
{
for(int i=65; i<75; i++) //i=65 that in ASCII 65 = A
{ // and 75 is K but it will less than 75 so it print till J
    for(int j=0; j<10-i+65; j++)
    { /* here i set j=0 and j < less than (10 - i) that i set to it decrease one by one so in this I add 65 in i so keep i zero at start and increase one by one */
        cout << (char)i; // to convert int to char so i write (char) before write variable
    }
    cout << endl; // new line use every time it print one alphabets
}
getch();
}

OUTPUT

Using Nested Loop

2012-01-05T07:53:00.000-08:00

Using Nested Loop

Nested Loop is using loop inside a loop like for loop is under for loop for example:
for(int i=0;i<10;i++)
{for(int j=0; j<4; j++)
{cout<<i;}
}

Above code is use like that first i value is 0 then condition true and then second loop is run it run for 4 times then increment is done and i value is 1 now and condition is true so it run again means the i loop run for 10 times and in every time i loop run 4 time second loop runs so total 40 times loop Run.
Check out Example of Number Triangle

#include<iostream.h>
#include<conio.h>
//Using Nested Loop
int main()
{
for(int i=1; i<10; i++) // i set to 1 and less than 10
{
   for(int j=0; j<i; j++) // j set to 0 and j less than i
   {
       cout << i;
   }
   cout << endl;
}
/* above code first i=1 and j=0 and it print 1 only one time because condition true that j < i (i=1) and new line
then increment is done and i value is now 2 and then j =0 and j<2 so it print i value 2 time and new line
Similarly it continue till i < 10. Check the output
*/
getch();
}

OUTPUT

Program : Show Sqaures of Number upto n terms

2012-01-01T23:13:00.000-08:00

Program : Show Sqaures of Number

This program first take input from user that an integer value and show the squares of term upto the number that enter by user like if i enter 2 then it display square of 1 and 2 and if i enter any number its show squares upto that term...

#include<iostream.h>
#include<conio.h>
int main()
{
int a;
cout << "Enter a Value upto you want to show squares of that number\n";
cin >> a;

//Using for Loop

for(int i =1; i <=a; i++)
{
cout << i << " Square is : " << i*i <<endl; // show square of that number
}
getch();
return 0;
}

OUTPUT:-
I enter Value 10

Introduction to Loop

2012-01-01T22:58:00.000-08:00

Introduction to Loop

Loop means to repeat again and again. In C++ there are three loops that While loop, do-While loop & For loop. In C++ loop continues while a condition is true. When condition becomes false, the loop ends and control passes to the statements following the loop.

There are three loop as i told before these are

For Loop:
This loop is easiest C++ loops to understand. This loop contain three parts first initialize , second condition & third increment.
Syntax:
for(initialize variable; condition ; variable increment)

like for(int i=0; i < 10; i++)
In this above statement 'i' variable is declared which have value 0 and 'i' gave condition that 'i' should less than 10 and then increment.
This works like that at begin its value is 0 and it execute the statement within the braces of for loop then increment is done and condition is check now i = 1 and i < 10 . It again run the code and this go on again and again.

Example :-

#include<iostream.h>
#include<conio.h>
int main()
{
for(int i=1; i <=10; i++) // don't put semicolon after for loop
{
cout<< i <<endl; // print value of i variable <<endl for new line
}
getch();
return 0;
}

Output :

While Loop
While loop is similar to for loop just little difference is there in while loop check the Syntax:
Syntax:

Initialize
While(condition)
statements 1;
statements 2;
increment;
}

like
int i=0;
while(i<10) //no semicolon
{
statement;
i++;

}

In Above we initialize 'i' value 0 first then while contain condition that i <10and if condition its true then code executes else it skip the loop and continue with program. and here it execute and run the statement 10 times.

Example:
#include<iostream.h>
#include<conio.h>
int main()
{
int i=1;
while(i<=10)
{
cout<< i <<endl; // print value of i variable <<endl for new line
i++;
}

getch();
return 0;
}

Output :

And Last
do-While Loop
Its different from other loop. In this loop Its first initialize then it execute, then increment & last condition is check. My mean to say that Code within do while loop execute at least one time if condition is true or false.
Syntax:
intialize
do
{
statement 1;
statement 2;
increment;
}while(condition); // semicolon at end

Check out example:

#include<iostream.h>
#include<conio.h>
int main()
{
int i=1; // initialize
do
{
cout << i<<endl; // print i value
i++; // increment
}while(i<=10); // check condition and semicolon at end
getch();
return 0;
}

Output :

Using Nested Condition

2011-12-29T00:36:00.000-08:00

Using Nested Condition

Nested Condition is if else condition that is used under if or else condition. Its condition within condition. Like : We have to check Something Like Someone DOB First i check date then Month and Then Year Three Statement check in One Condition.
Check out One Example For Better Understand.

#include<iostream.h>

#include<conio.h>

int main()

{
int number;
cout << "Enter Any Number\n";
cin >> number;

if(number >10) // check number greater than 10
{
if(number <100) // check number less than 100
{
cout << "Number is Between 10-100";
}
}

else
{
if(number<10) // check number less than 10
{
cout << "Number is less than 10";
}
}

getch();

return 0;

}

OUTPUT

Using else if statement

2011-12-29T00:04:00.000-08:00

Using else if statement

Else if statement is similar to if condition. In else-if condition you can give more than one condition like we have to give grade if students score greater than 90 got A grade, b/w 70-90 got B grade , 50-70 got C grade and so on. it require more than one condition. So we use else if condition check out example for better understand.

#include<iostream.h>
#include<conio.h>
int main()
{
int eng,sc,maths;
float percentage;
cout << "Enter Marks of student in\n";
cout << "In english \n";
cin>> eng;
cout << "In Science\n";
cin>>sc;
cout <<"In maths\n";
cin >> maths;
percentage = (sc+maths+eng)/3; // %age formula (total / 300) * 100

if(percentage > 90) // check condition
{
cout << "A Grade\n";
}
else if(percentage > 70)//similar to if also check condition
{
cout << "B Grade\n";
}
else if(percentage > 50)
{
cout<< " C Grade\n";
}
else if(percentage > 40)
{
cout << "D Grade\n";
}
else
{
cout << "E Grade\n";
}
getch();
return 0;
}

OUTPUT

Using Conditional Statements

2011-12-28T04:45:00.000-08:00

Using Conditional Statements

The if statement is used to check the condition. If Condition is true Then particular code execute and if condition is not true then it pass to else statement, and that code is execute within else. & else statement is not necessary every time. Check Out One Program to better Understand

#include<iostream.h>
#include<conio.h>
int main()
{
int a; //a integer variable define
cout << "Enter Any Number\n";
cin >> a; // take value in a

if(a%2 == 0) //check if a%2 == 0 then code execute

/* a%2 means value of a divide by 2 and if the remainder comes out to be zero then its display its Even Number.

*/
{
cout << "Its Even Number\n";
} // code should be written in braces
else

/* Else Dont Require any argument So you need to type else only and rest of code that execute if, if statement is false

Here if a%2 is other than 0 then its show Its Odd Number.

*/
{
cout << "Its Odd Number\n";
}
getch();
return 0;
}

OUTPUT

Program : Using #define Function

2011-12-20T05:41:00.000-08:00

Using #define Function

#define use to define a function or value or any work that particular keyword replace with that work like to display on screen i always use cout << everytime i replace it with a keyword print so next time when i require cout << then i have to use only print rest all is same like print "AZ"; //it will print AZ. Check Out Program.

Let Check Out Example :-

//Using #define function
#include<iostream.h>
#include<conio.h>

#define pi 3.14
/* Here i Define a Variable pi which i assign a value that 3.14(here)
*/
#define print cout <<
/* It must declare after Header File
Syntax :-
#define variable_name function or value

Like here i define variable print which function is to replace cout <<
So i dont have to write cout << i can write directly print check out main function*/

int main()
{
print pi; // print = cout << and pi = 3.14
// it will print 3.14 on screen
print "\nHello world"; // print hello world
getch();
return 0;
}

Output

Program : Using Bool Data Type

2011-12-20T05:34:00.000-08:00

Using Bool Data Type

Bool data type can store two value only 0 or 1. o for False & 1 For True. if define Bool variable and that variable contain value more than 1 it store only 1 like i declare bool variable az = 1212313; it store az = 1 or az = true; it store az =1 & it shows zero when its False or value is Zero only.

Let Check Out Example :-

#include<iostream.h>
#include<conio.h>
int main()
{
    //Using Bool Data Type
    bool a = 321, b; /*Declare two bool variable. Bool store two type of value true or falue and this show
    bu integer value 1 for true and 0 for false like here i initialize bool a
    with 321 value it store 1 in it let see*/
    cout << "Bool a Contains : " << a; // print a it show 1
    int c = true; // it store value 1 for true and 0 for false
    c = a + a; // a value is 1 and 1 add to 1 gives 2
    cout << "\nInteger c contain : " << c; //print c value
    b = c + a;
/* it 2 + 1 it give 1 because its type is bool so it show only 0 and 1*/
    cout << "\nBool b contain : " <<b;

    getch();
    return 0;
}

Output

Assignment & Increment/Decrement Operators

2011-12-16T05:39:00.000-08:00

Assignment & Increment/Decrement Operators

This operators are used to shorten the code. Assignment Operators are used to assign value with arithmetic operators & Increment or Decrement used to increase by 1 or decrease by 1 using ++ or -- sign

you can learn more check out following program:-

#include<iostream.h>
#include<conio.h>
int main()
{
int a = 10, b = 20; // declare and assign value to variable

a += b; // this means a = a + b
cout << a<<endl; // print 30
a -= b; // this means a = a - b
cout << a<<endl; // print 10

a *= b; // this means a = a * b

cout << a<<endl; // print 200

a /= b; // this means a = a / b

cout << a <<endl; // print 10

//using Increment and Decrement Operators

a++;
cout << a <<endl;   // print 11
cout << a++ <<endl;   // print 11
cout << a <<endl;   //print 12
cout << ++a <<endl;   // print 13

/* AS you see last four line as i cout a it shows 11 when i use a++ then also its shows 11 this is because when we use a++ its value remain same at that part or that time of declaration. This is known as post-increment. It Increase Value by 1 later of declaration. Like here after cout a++ on next line i cout << a; its shows value of a with 1 increment. & after that i use ++a this is pre-increment and this increase value by 1 at the same time it show 13*/

a--; // now a = 13
cout << a <<endl;   // print 12
cout << a-- <<endl;   // print 12
cout << a <<endl;   //print 11
cout << --a <<endl;   // print 10
/* Here also concept is same of increment but difference is that there is increase by 1 but here decrease by 1 with same concept
*/

getch();
return 0;
}

OUTPUT

Program : Using Arithmetic Operators

2011-12-16T03:53:00.000-08:00

Program : Using Arithmetic Operators

Arithmetic Operators
There are mainly Four Arithmetic Operators in C++ i.e. are + , - , * & /. + for Addition , - for Subtraction , * for Multiply & / for Divide.

Check the Following Program :-

#include<iostream.h>
#include<conio.h> // for getch()
int main()
{
float a , b; // define float variable
cout << "Enter 1st Number \n";
cin >> a; // take value in a variable
cout << "Enter 2nd Number \n";
cin >> b; //take value in b variable
cout << "Addition = " << a + b <<endl; /* Display Addition value of a & b variable*/
cout << "Subtraction = " << a - b <<endl; /* Display Subtracted value of a & b variable*/
cout << "Multiply = " << a * b <<endl; /* Display Multiply value of a & b variable*/
cout << "Divide = " << a / b <<endl; /* Display Divided value of a & b variable*/

getch();
return 0;
}

OUTPUT