C programming interview questions and answers

How to run c program

2011-12-11T11:38:00.001+05:30

To compile and run a program may vary according to complier and IDE.

Turbo c++ 4.5

To compile: ALT + F9 or go to Project -> Compile

To run: CTRL + F9 or go to Debug -> Run

Turbo c++ 3.0

To compile: ALT + F9 or go to Compile -> Compile

To run: CTRL + F9 or go to Run -> Run

Suppose name of c file is demo.c

Linux gcc:

To compile: gcc demo.c

To run: ./a.out

Visual c++:

Open the Visual Studio Command Prompt

To compile: cpp demo.c

To run: demo

Free c program download

2011-12-11T06:18:00.001+05:30

You can free download the big collection of c programs.

It is Microsoft office word 2007 format (.docx)

How to download it: Click on following download link and go the file menu and choose download original.

For doc format: Download

C program for bubble sort

2011-12-11T06:11:00.001+05:30

Bubble sort program in c

#include<stdio.h>

int main(){

int s,temp,i,j,a[20];

printf("Enter total numbers of elements: ");

scanf("%d",&s);

printf("Enter %d elements: ",s);

for(i=0;i<s;i++)

scanf("%d",&a[i]);

//Bubble sorting algorithm

for(i=s-2;i>=0;i--){

for(j=0;j<=i;j++){

if(a[j]>a[j+1]){

temp=a[j];

a[j]=a[j+1];

a[j+1]=temp;

}

printf("After sorting: ");

for(i=0;i<s;i++)

printf(" %d",a[i]);

return 0;

}

Output:

Enter total numbers of elements: 5

Enter 5 elements: 6 2 0 11 9

After sorting: 0 2 6 9 11

1. Write a c program for bubble sort.

2. Write a c program for insertion sort.

3. Write a c program for selection sort.

4. Write a c program for quick sort.

5. Write a c program for heap sort.

6. Write a c program for merge sort.

7. Write a c program for shell sort.

8. Big list of c program examples

C program for Pascal triangle

2011-12-11T06:05:00.001+05:30

Program for Pascal triangle in c

#include<stdio.h>

int main(){

int line,i,j,k;

printf("Enter the no. of lines: ");

scanf("%d",&line);

for(i=1;i<=line;i++){

for(j=1;j<=line-i;j++)

printf(" ");

for(k=1;k<i;k++)

printf("%d",k);

for(k=i;k>=1;k--)

printf("%d",k);

printf("\n");

}

return 0;

}

Sample output:
Enter the no. of lines: 5

121

12321

1234321

123454321

Basic c program

2011-12-11T05:59:00.001+05:30

C program to print "hello world"

C program to add two given numbers

C program to accept a string from users and print it

C program to check a given number is positive or negative

C program to swap two numbers

C program to print numbers from 1 to 10

C program to print numbers from 1 to 10 in reverse order

C program to print all even numbers of the given range

C program to accept a string and find out total numbers of characters

C program to add n natural numbers from 1

C program to get the marks of students and print the average marks

C program to print the all elements of any array

C program to find square root of a number

C program to find max of two unequal numbers

2011-12-11T05:48:00.002+05:30

#include<stdio.h>

int main(){

    int a,b,max;

    scanf("%d %d",&a,&b);

    if(a > b)

         max = a;

    else

         max = b;

    printf("%d",max));

    return 0;

}

C program to find square root of a number

2011-12-11T05:47:00.002+05:30

#include<stdio.h>

#include<math.h>

int main(){

    int num;

    scanf("%d",&num);

    printf("Square root: %f",sqrt(num));

    return 0;

}

C program to print the all elements of any array

2011-12-11T05:46:00.002+05:30

#include<stdio.h>

int main(){

int arr[]={1,2,34,56,89};

int i;

    for(i=0;i<5;i++){

        printf("%d ",arr[i]);

}

    return 0;

}

C program to get the marks of students and print the average marks

2011-12-11T05:45:00.002+05:30

#include<stdio.h>

int main(){

int n;

float marks, sum = 0;

    printf("Enter any total numbers of student: ");

    scanf("%d",&n);

    for(i=1;i<=n;i++){

        printf("Enter marks of student %d: ",i);

       scanf("%f",&marks);

       sum = sum + marks;

}

printf("Average marks: %f",sum/n);

    return 0;

}

C program to add n natural numbers from 1

2011-12-11T05:44:00.002+05:30

#include<stdio.h>

int main(){

int n,sum = 0;

    printf("Enter any positive number: ");

    scanf("%d",&n);

    for(i=1;i<=n;i++){

        sum = sum + 1;

}

printf("Sum of n numbers: %s",sum);

    return 0;

}

C program to accept a string and find out total numbers of characters

2011-12-11T05:43:00.002+05:30

#include<stdio.h>

#include<string.h>

int main(){

    char str[20];

    printf("Enter any string: ");

    scanf("%s",&str);

    printf("Length of string: %d",strlen(str));

    return 0;

}

C program to print all even numbers of the given range

2011-12-11T05:42:00.002+05:30

#include<stdio.h>

int main(){

    into min,max;

    printf("Enter min and max even numbers respectively: ");

    scanf("%d %d",&min,&max);

    for(i=min;i<=max;i=i+2){

        printf("%d ",i);

}

    return 0;

}

C program to print numbers from 1 to 10 in reverse order

2011-12-11T05:41:00.000+05:30

#include<stdio.h>

int main(){

int i;

    for(i=10;i>= 0;i--){

        printf("%d ",i);

    }

    return 0;

}

C program to print numbers from 1 to 10

2011-12-11T05:40:00.000+05:30

#include<stdio.h>

int main(){

int i;

    for(i=1;i<=10;i++){

        printf("%d ",i);

}

    return 0;

}

C program to swap two numbers

2011-12-11T05:38:00.000+05:30

#include<stdio.h>

int main(){

    int a,b,c;

    scanf("%d %d",&a,&b);

    c = a;

    a = b;

    b = c;

    printf("%d %d",a,b);

    return 0;

}

C program to check a given number is positive or negative

2011-12-11T05:36:00.000+05:30

#include<stdio.h>

int main(){

    int num;

    scanf("%d",&num);

    if(num ==0)

         printf("Number is zero.");

    else if(num > 0)

printf("Number is positive.");

else

printf("Number is negative.");

    return 0;

}

Algorithm:

A number greater than zero is called positive number while a number less than zero is called negative number. Zero is neither positive number nor negative number it at the boundary of positive number and negative number.

C program to accept a string from users and print it

2011-12-11T05:32:00.000+05:30

C program to print a text

#include<stdio.h>

int main(){

    char str[20];

    scanf("%s",&str);

    printf("%s",str);

    return 0;

}

C program to add two given numbers

2011-12-11T05:31:00.002+05:30

#include<stdio.h>

int main(){

    int a,b,sum;

    scanf("%d %d",&a,&b);

    sum = a + b;

    printf("%d",sum);

    return 0;

}

C program to print "hello world"

2011-12-11T05:30:00.000+05:30

One the most basic program of c language is print
Hello world.

#include<stdio.h>

int main(){

    printf("Hello world");

    return 0;

}

C program for merge sort

2011-12-11T05:25:00.000+05:30

#include<stdio.h>

#define MAX 50

void mergeSort(int arr[],int low,int mid,int high);

void partition(int arr[],int low,int high);

int main(){

int merge[MAX],i,n;

printf("Enter the total number of elements: ");

scanf("%d",&n);

printf("Enter the elements which to be sort: ");

for(i=0;i<n;i++){

scanf("%d",&merge[i]);

}

partition(merge,0,n-1);

printf("After merge sorting elements are: ");

for(i=0;i<n;i++){

printf("%d ",merge[i]);

}

return 0;

}

void partition(int arr[],int low,int high){

int mid;

if(low<high){

mid=(low+high)/2;

partition(arr,low,mid);

partition(arr,mid+1,high);

mergeSort(arr,low,mid,high);

}

void mergeSort(int arr[],int low,int mid,int high){

int i,m,k,l,temp[MAX];

l=low;

i=low;

m=mid+1;

while((l<=mid)&&(m<=high)){

if(arr[l]<=arr[m]){

temp[i]=arr[l];

l++;

}

else{

temp[i]=arr[m];

m++;

}

i++;

}

if(l>mid){

for(k=m;k<=high;k++){

temp[i]=arr[k];

i++;

}

else{

for(k=l;k<=mid;k++){

temp[i]=arr[k];

i++;

}

for(k=low;k<=high;k++){

arr[k]=temp[k];

}

Sample output:

Enter the total number of elements: 5

Enter the elements which to be sort: 2 5 0 9 1

After merge sorting elements are: 0 1 2 5 9

1. Write a c program for bubble sort.

2. Write a c program for insertion sort.

3. Write a c program for selection sort.

4. Write a c program for quick sort.

5. Write a c program for heap sort.

6. Write a c program for merge sort.

7. Write a c program for shell sort.

8. Big list of c program examples

C program for matrix multiplication

2011-12-11T05:22:00.000+05:30

#include<stdio.h>

int main(){

int a[5][5],b[5][5],c[5][5],i,j,k,sum=0,m,n,o,p;

printf("\nEnter the row and column of first matrix");

scanf("%d %d",&m,&n);

printf("\nEnter the row and column of second matrix");

scanf("%d %d",&o,&p);

if(n!=o){

printf("Matrix mutiplication is not possible");

printf("\nColumn of first matrix must be same as row of second matrix");

}

else{

printf("\nEnter the First matrix->");

for(i=0;i<m;i++)

for(j=0;j<n;j++)

scanf("%d",&a[i][j]);

printf("\nEnter the Second matrix->");

for(i=0;i<o;i++)

for(j=0;j<p;j++)

scanf("%d",&b[i][j]);

printf("\nThe First matrix is\n");

for(i=0;i<m;i++){

printf("\n");

for(j=0;j<n;j++){

printf("%d\t",a[i][j]);

}

printf("\nThe Second matrix is\n");

for(i=0;i<o;i++){

printf("\n");

for(j=0;j<p;j++){

printf("%d\t",b[i][j]);

}

for(i=0;i<m;i++)

for(j=0;j<p;j++)

c[i][j]=0;

for(i=0;i<m;i++){ //row of first matrix

for(j=0;j<p;j++){ //column of second matrix

sum=0;

for(k=0;k<n;k++)

sum=sum+a[i][k]*b[k][j];

c[i][j]=sum;

}

printf("\nThe multiplication of two matrix is\n");

for(i=0;i<m;i++){

printf("\n");

for(j=0;j<p;j++){

printf("%d\t",c[i][j]);

}

return 0;

}

Algorithm:

Multiplication of two matrixes:

Rule: Multiplication of two matrixes is only possible if first matrix has size m X n and other matrix has size n x r. Where m, n and r are any positive integer.

Multiplication of two matrixes is defined as