C Programs

C program to check odd or even using modulus operator


#include <stdio.h>
int main(){
 int n;
printf("Enter an integer\n");
 scanf("%d", &n);
if (n%2 == 0)
 printf("Even\n");
 else
 printf("Odd\n");
return 0;
}


 //Program for addition,sub,multiply,divide.
 #include <stdio.h>
int main()
{
 int first, second, add, subtract, multiply;
 float divide;
printf("Enter two integers\n");
 scanf("%d%d", &first, &second);
add = first + second;
 subtract = first - second;
 multiply = first * second;
 divide = first / (float)second; //typecasting
printf("Sum = %d\n",add);
 printf("Difference = %d\n",subtract);
 printf("Multiplication = %d\n",multiply);
 printf("Division = %.2f\n",divide);
return 0;
}

 C program to check whether input alphabet is a vowel or not

#include <stdio.h>
 
int main()
{
  char ch;
 
  printf("Enter a character\n");
  scanf("%c", &ch);
 
  if (ch == 'a' || ch == 'A' || ch == 'e' || ch == 'E' || ch == 'i' || ch == 'I' || ch =='o' || ch=='O' || ch == 'u' || ch == 'U')
    printf("%c is a vowel.\n", ch);
  else
    printf("%c is not a vowel.\n", ch);
 
  return 0;
}

Check vowel using switch statement

#include <stdio.h>
int main()
{
 char ch;
printf("Enter a character\n");
 scanf("%c", &ch);
if (ch == 'a' || ch == 'A' || ch == 'e' || ch == 'E' || ch == 'i' || ch == 'I' || ch =='o' || ch=='O' || ch == 'u' || ch == 'U')
 printf("%c is a vowel.\n", ch);
 else

 printf("%c is not a vowel.\n", ch);
return 0;
}
Check vowel using switch statement

#include <stdio.h>
 
int main()
{
  char ch;
 
  printf("Input a character\n");
  scanf("%c", &ch);
 
  switch(ch)
  {
    case 'a':
    case 'A':
    case 'e':
    case 'E':
    case 'i':
    case 'I':
    case 'o':
    case 'O':
    case 'u':
    case 'U':
      printf("%c is a vowel.\n", ch);
      break;
    default:
      printf("%c is not a vowel.\n", ch);
  }              
 
  return 0;
}

Program to check vowel or not Program Using function

int check_vowel(char a)
{
    if (a >= 'A' && a <= 'Z')
       a = a + 'a' - 'A';   /* Converting to lower case or use a = a + 32 */
 
    if (a == 'a' || a == 'e' || a == 'i' || a == 'o' || a == 'u')
       return 1;
 
    return 0;
}


This function can also be used to check if a character is a consonant or not, if it's not a vowel then it will be a consonant, but make sure that the character is an alphabet not a special character.


Factorial program in c using for loop

#include <stdio.h>
 
int main()
{
  int c, n, fact = 1;
 
  printf("Enter a number to calculate it's factorial\n");
  scanf("%d", &n);
 
  for (c = 1; c <= n; c++)
    fact = fact * c;
 
  printf("Factorial of %d = %d\n", n, fact);
 
  return 0;
}



Factorial program in c using function



#include <stdio.h>
 
long factorial(int);
 
int main()
{
  int number;
  long fact = 1;
 
  printf("Enter a number to calculate it's factorial\n");
  scanf("%d", &number);
 
  printf("%d! = %ld\n", number, factorial(number));
 
  return 0;
}
 
long factorial(int n)
{
  int c;
  long result = 1;
 
  for (c = 1; c <= n; c++)
    result = result * c;
 
  return result;
}


Factorial program in c using recursion

#include<stdio.h>
 
long factorial(int);
 
int main()
{
  int n;
  long f;
 
  printf("Enter an integer to find factorial\n");
  scanf("%d", &n); 
 
  if (n < 0)
    printf("Negative integers are not allowed.\n");
  else
  {
    f = factorial(n);
    printf("%d! = %ld\n", n, f);
  }
 
  return 0;
}
 
long factorial(int n)
{
  if (n == 0)
    return 1;
  else
    return(n * factorial(n-1));
}





Program for floyd's triangle

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#include <stdio.h>
 
int main()
{
  int n, i,  c, a = 1;
 
  printf("Enter the number of rows of Floyd's triangle to print\n");
  scanf("%d", &n);
 
  for (i = 1; i <= n; i++)
  {
    for (c = 1; c <= i; c++)
    {
      printf("%d ",a);
      a++;
    }
    printf("\n");
  }
 
  return 0;
}

Factorial program in c using for loop

Factorial program in c using for loop

#include <stdio.h>
 
int main()
{
  int c, n, fact = 1;
 
  printf("Enter a number to calculate it's factorial\n");
  scanf("%d", &n);
 
  for (c = 1; c <= n; c++)
    fact = fact * c;
 
  printf("Factorial of %d = %d\n", n, fact);
 
  return 0;
}

Factorial program in c using function



#include <stdio.h>
 
long factorial(int);
 
int main()
{
  int number;
  long fact = 1;
 
  printf("Enter a number to calculate it's factorial\n");
  scanf("%d", &number);
 
  printf("%d! = %ld\n", number, factorial(number));
 
  return 0;
}
 
long factorial(int n)
{
  int c;
  long result = 1;
 
  for (c = 1; c <= n; c++)
    result = result * c;
 
  return result;
}


Factorial program in c using recursion

#include<stdio.h>
 
long factorial(int);
 
int main()
{
  int n;
  long f;
 
  printf("Enter an integer to find factorial\n");
  scanf("%d", &n); 
 
  if (n < 0)
    printf("Negative integers are not allowed.\n");
  else
  {
    f = factorial(n);
    printf("%d! = %ld\n", n, f);
  }
 
  return 0;
}
 
long factorial(int n)
{
  if (n == 0)
    return 1;
  else
    return(n * factorial(n-1));
}

#include <stdio.h>

int main()
{
int c, n, fact = 1;

printf("Enter a number to calculate it's factorial\n");
scanf("%d", &n);

for (c = 1; c <= n; c++)
fact = fact * c;

printf("Factorial of %d = %d\n", n, fact);

return 0;
}
Factorial program in c using function

#include <stdio.h>

long factorial(int);

int main()
{
int number;
long fact = 1;

printf("Enter a number to calculate it's factorial\n");
scanf("%d", &number);

printf("%d! = %ld\n", number, factorial(number));

return 0;
}

long factorial(int n)
{
int c;
long result = 1;

for (c = 1; c <= n; c++)
result = result * c;

return result;
}

Factorial program in c using recursion

#include<stdio.h>
 
long factorial(int);
 
int main()
{
  int n;
  long f;
 
  printf("Enter an integer to find factorial\n");
  scanf("%d", &n); 
 
  if (n < 0)
    printf("Negative integers are not allowed.\n");
  else
  {
    f = factorial(n);
    printf("%d! = %ld\n", n, f);
  }
 
  return 0;
}
 
long factorial(int n)
{
  if (n == 0)
    return 1;
  else
    return(n * factorial(n-1));
}

Factorial using Recursion

#include<stdio.h>

long factorial(int);

int main()
{
int n;
long f;

printf("Enter an integer to find factorial\n");
scanf("%d", &n);

if (n < 0)
printf("Negative integers are not allowed.\n");
else
{
f = factorial(n);
printf("%d! = %ld\n", n, f);
}

return 0;
}

long factorial(int n)
{
if (n == 0)
return 1;
else
return(n * factorial(n-1));

}

  Program for floyd's triangle

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#include <stdio.h>

int main()
{
int n, i, c, a = 1;

printf("Enter the number of rows of Floyd's triangle to print\n");
scanf("%d", &n);

for (i = 1; i <= n; i++)
{
for (c = 1; c <= i; c++)
{
printf("%d ",a);
a++;
}
printf("\n");
}

return 0;
}

 Program to reverse a number

#include <stdio.h>

int main()
{
int n, reverse = 0;

printf("Enter a number to reverse\n");
scanf("%d", &n);

while (n != 0)
{
reverse = reverse * 10;
reverse = reverse + n%10;
n = n/10;
}

printf("Reverse of entered number is = %d\n", reverse);

 

  return 0;
}

return 0;
}

Palindrome number program c

#include <stdio.h>
 
int main()
{
   int n, reverse = 0, temp;
 
   printf("Enter a number to check if it is a palindrome or not\n");
   scanf("%d",&n);
 
   temp = n;
 
   while( temp != 0 )
   {
      reverse = reverse * 10;
      reverse = reverse + temp%10;
      temp = temp/10;
   }
 
   if ( n == reverse )
      printf("%d is a palindrome number.\n", n);
   else
      printf("%d is not a palindrome number.\n", n);
 
   return 0;
}

Program to check number palindrome or not?

#include <stdio.h>

int main()
{
int n, reverse = 0, temp;

printf("Enter a number to check if it is a palindrome or not\n");
scanf("%d",&n);

temp = n;

while( temp != 0 )
{
reverse = reverse * 10;
reverse = reverse + temp%10;
temp = temp/10;
}

if ( n == reverse )
printf("%d is a palindrome number.\n", n);
else
printf("%d is not a palindrome number.\n", n);

return 0;
} C program to calculate sum of 5 subjects

   int s1, s2, s3, s4, s5, sum, total = 500;

   float per;

   scanf("%d %d %d %d %d", &s1, &s2, &s3, &s4, &s5);

   printf("\nSum : %d", sum);

   printf("\nPercentage : %f", per);

}

Program to find biggest of 3 number.

/*
 * C program to find the biggest of three numbers
 */
#include <stdio.h>

void main()
{
int num1, num2, num3;

printf("Enter the values of num1, num2 and num3\n");
scanf("%d %d %d", &num1, &num2, &num3);
printf("num1 = %d\tnum2 = %d\tnum3 = %d\n", num1, num2, num3);
if (num1 > num2)
{
if (num1 > num3)
{
printf("num1 is the greatest among three \n");
}
else
{
printf("num3 is the greatest among three \n");
}
}
else if (num2 > num3)
printf("num2 is the greatest among three \n");
else
printf("num3 is the greatest among three \n");
}

C Program to Print Armstrong Number from 1 to 1000

 */
#include <stdio.h>

main()
{
int number, temp, digit1, digit2, digit3;

printf("Print all Armstrong numbers between 1 and 1000:\n");
number = 001;
while (number <= 900)
{
digit1 = number - ((number / 10) * 10);
digit2 = (number / 10) - ((number / 100) * 10);
digit3 = (number / 100) - ((number / 1000) * 10);
temp = (digit1 * digit1 * digit1) + (digit2 * digit2 * digit2) + (digit3 * digit3 * digit3);
if (temp == number)
{
printf("\n Armstrong no is:%d", temp);
}
number++;
}
}

This function can also be used to check if a character is a consonant or not, if it's not a vowel then it will be a consonant, but make sure that the character is an alphabet not a special character.






Program to calculate sum of five subjects 

#include<stdio.h>

int main() {

   int s1, s2, s3, s4, s5, sum, total = 500;

   float per;

   printf("\nEnter marks of 5 subjects : ");

   scanf("%d %d %d %d %d", &s1, &s2, &s3, &s4, &s5);

   sum = s1 + s2 + s3 + s4 + s5;

   printf("\nSum : %d", sum);

   per = (sum * 100) / total;

   printf("\nPercentage : %f", per);

   return (0);

}





Program for subtraction of two matrices


#include<stdio.h>

int main() {
   int i, j, mat1[10][10], mat2[10][10], mat3[10][10];
   int row1, col1, row2, col2;

   printf("\nEnter the number of Rows of Mat1 : ");
   scanf("%d", &row1);
   printf("\nEnter the number of Cols of Mat1 : ");
   scanf("%d", &col1);

   printf("\nEnter the number of Rows of Mat2 : ");
   scanf("%d", &row2);
   printf("\nEnter the number of Columns of Mat2 : ");
   scanf("%d", &col2);

   /* Before accepting the Elements Check if no of
    rows and columns of both matrices is equal */
   if (row1 != row2 || col1 != col2) {
      printf("\nOrder of two matrices is not same ");
      exit(0);
   }

   //Accept the Elements in Matrix 1
   for (i = 0; i < row1; i++) {
      for (j = 0; j < col1; j++) {
         printf("Enter the Element a[%d][%d] : ", i, j);
         scanf("%d", &mat1[i][j]);
      }
   }

   //Accept the Elements in Matrix 2
   for (i = 0; i < row2; i++)
      for (j = 0; j < col2; j++) {
         printf("Enter the Element b[%d][%d] : ", i, j);
         scanf("%d", &mat2[i][j]);
      }

   //Subtraction of two matrices
   for (i = 0; i < row1; i++)
      for (j = 0; j < col1; j++) {
         mat3[i][j] = mat1[i][j] - mat2[i][j];
      }

   //Print out the Resultant Matrix
   printf("\nThe Subtraction of two Matrices is : \n");
   for (i = 0; i < row1; i++) {
      for (j = 0; j < col1; j++) {
         printf("%d\t", mat3[i][j]);
      }
      printf("\n");
   }

   return (0);
}

Program to add two matrices (2X2)

#include <stdio.h>
 
int main()
{
   int m, n, c, d, first[10][10], second[10][10], sum[10][10];
 
   printf("Enter the number of rows and columns of matrix\n");
   scanf("%d%d", &m, &n);
   printf("Enter the elements of first matrix\n");
 
   for (c = 0; c < m; c++)
      for (d = 0; d < n; d++)
         scanf("%d", &first[c][d]);
 
   printf("Enter the elements of second matrix\n");
 
   for (c = 0; c < m; c++)
      for (d = 0 ; d < n; d++)
            scanf("%d", &second[c][d]);
 
   printf("Sum of entered matrices:-\n");
 
   for (c = 0; c < m; c++) {
      for (d = 0 ; d < n; d++) {
         sum[c][d] = first[c][d] + second[c][d];
         printf("%d\t", sum[c][d]);
      }
      printf("\n");
   }
 
   return 0;
}




Program for matrix multiplication




#include <stdio.h>
 
int main()
{
  int m, n, p, q, c, d, k, sum = 0;
  int first[10][10], second[10][10], multiply[10][10];
 
  printf("Enter the number of rows and columns of first matrix\n");
  scanf("%d%d", &m, &n);
  printf("Enter the elements of first matrix\n");
 
  for (c = 0; c < m; c++)
    for (d = 0; d < n; d++)
      scanf("%d", &first[c][d]);
 
  printf("Enter the number of rows and columns of second matrix\n");
  scanf("%d%d", &p, &q);
 
  if (n != p)
    printf("Matrices with entered orders can't be multiplied with each other.\n");
  else
  {
    printf("Enter the elements of second matrix\n");
 
    for (c = 0; c < p; c++)
      for (d = 0; d < q; d++)
        scanf("%d", &second[c][d]);
 
    for (c = 0; c < m; c++) {
      for (d = 0; d < q; d++) {
        for (k = 0; k < p; k++) {
          sum = sum + first[c][k]*second[k][d];
        }
 
        multiply[c][d] = sum;
        sum = 0;
      }
    }
 
    printf("Product of entered matrices:-\n");
 
    for (c = 0; c < m; c++) {
      for (d = 0; d < q; d++)
        printf("%d\t", multiply[c][d]);
 
      printf("\n");
    }
  }
 
  return 0;
}




Program for transpose of a matrix
#include <stdio.h>
 
int main()
{
   int m, n, c, d, matrix[10][10], transpose[10][10];
 
   printf("Enter the number of rows and columns of matrix\n");
   scanf("%d%d", &m, &n);
 
   printf("Enter the elements of matrix\n");
 
   for (c = 0; c < m; c++)
      for(d = 0; d < n; d++)
         scanf("%d",&matrix[c][d]);
 
   for (c = 0; c < m; c++)
      for( d = 0 ; d < n ; d++ )
         transpose[d][c] = matrix[c][d];
 
   printf("Transpose of entered matrix :-\n");
 
   for (c = 0; c < n; c++) {
      for (d = 0; d < m; d++)
         printf("%d\t",transpose[c][d]);
      printf("\n");
   }
 
   return 0;
}
Program for inserting an element in an  array




#include <stdio.h>
 
int main()
{
   int m, n, c, d, matrix[10][10], transpose[10][10];
 
   printf("Enter the number of rows and columns of matrix\n");
   scanf("%d%d", &m, &n);
 
   printf("Enter the elements of matrix\n");
 
   for (c = 0; c < m; c++)
      for(d = 0; d < n; d++)
         scanf("%d",&matrix[c][d]);
 
   for (c = 0; c < m; c++)
      for( d = 0 ; d < n ; d++ )
         transpose[d][c] = matrix[c][d];
 
   printf("Transpose of entered matrix :-\n");
 
   for (c = 0; c < n; c++) {
      for (d = 0; d < m; d++)
         printf("%d\t",transpose[c][d]);
      printf("\n");
   }
 
   return 0;
}


Program to delete an element from an array

#include <stdio.h>
 
int main()
{
   int array[100], position, c, n;
 
   printf("Enter number of elements in array\n");
   scanf("%d", &n);
 
   printf("Enter %d elements\n", n);
 
   for ( c = 0 ; c < n ; c++ )
      scanf("%d", &array[c]);
 
   printf("Enter the location where you wish to delete element\n");
   scanf("%d", &position);
 
   if ( position >= n+1 )
      printf("Deletion not possible.\n");
   else
   {
      for ( c = position - 1 ; c < n - 1 ; c++ )
         array[c] = array[c+1];
 
      printf("Resultant array is\n");
 
      for( c = 0 ; c < n - 1 ; c++ )
         printf("%d\n", array[c]);
   }
 
   return 0;
}

Program to reverse elements in an array

#include <stdio.h>
 
int main()
{
   int n, c, d, a[100], b[100];
 
   printf("Enter the number of elements in array\n");
   scanf("%d", &n);
 
   printf("Enter the array elements\n");
 
   for (c = 0; c < n ; c++)
      scanf("%d", &a[c]);
 
   /*
    * Copying elements into array b starting from end of array a
    */
 
   for (c = n - 1, d = 0; c >= 0; c--, d++)
      b[d] = a[c];
 
   /*
    * Copying reversed array into original.
    * Here we are modifying original array, this is optional.
    */
 
   for (c = 0; c < n; c++)
      a[c] = b[c];
 
   printf("Reverse array is\n");
 
   for (c = 0; c < n; c++)
      printf("%d\n", a[c]);
 
   return 0;
}

Program to read a file and print it content on screen

#include <stdio.h>
#include <stdlib.h>
 
int main()
{
   char ch, file_name[25];
   FILE *fp;
 
   printf("Enter the name of file you wish to see\n");
   gets(file_name);
 
   fp = fopen(file_name,"r"); // read mode
 
   if( fp == NULL )
   {
      perror("Error while opening the file.\n");
      exit(EXIT_FAILURE);
   }
 
   printf("The contents of %s file are :\n", file_name);
 
   while( ( ch = fgetc(fp) ) != EOF )
      printf("%c",ch);
 
   fclose(fp);
   return 0;
}

CREATE A FILE AND STORE DATA IN IT IN C PROGRAM


#include<stdio.h>

int main(){

FILE *fp;

char ch;

fp=fopen("file.txt","w");

printf("\nEnter data to be stored in to the file:");

while((ch=getchar())!=EOF)

putc(ch,fp);

fclose(fp);

return 0;

}

Program to write data to a file and read the data from the file

#include<stdio.h>

struct Student {
   int roll;
   char name[12];
   int percent;
} s1 = { 10, "SMJC", 80 };

int main() {
   FILE *fp;
   struct Student s2;

   //Write details of s1 to file
   fp = fopen("ip.txt", "w");
   fwrite(&s1, sizeof(s1), 1, fp);
   fclose(fp);

   fp = fopen("ip.txt", "r");
   fread(&s2, sizeof(s2), 1, fp);
   fclose(fp);

   printf("\nRoll : %d", s2.roll);
   printf("\nName : %s", s2.name);
   printf("\nPercent : %d", s2.percent);

   return (0);
}

Write a C program to read name and marks of n number of students from user and store them in a file


#include <stdio.h>
int main(){
   char name[50];
   int marks,i,n;
   printf("Enter number of students: ");
   scanf("%d",&n);
   FILE *fptr;
   fptr=(fopen("C:\\student.txt","w"));
   if(fptr==NULL){
       printf("Error!");
       exit(1);
   }
   for(i=0;i<n;++i)
   {
      printf("For student%d\nEnter name: ",i+1);
      scanf("%s",name);
      printf("Enter marks: ");
      scanf("%d",&marks);
      fprintf(fptr,"\nName: %s \nMarks=%d \n",name,marks);
   }
   fclose(fptr);
   return 0;
}





Write a C program to read name and marks of n number of students from user and store them in a file. If the file previously exits, add the information of n students.


#include <stdio.h>
int main(){
   char name[50];
   int marks,i,n;
   printf("Enter number of students: ");
   scanf("%d",&n);
   FILE *fptr;
   fptr=(fopen("C:\\student.txt","a"));
   if(fptr==NULL){
       printf("Error!");
       exit(1);
   }
   for(i=0;i<n;++i)
   {
      printf("For student%d\nEnter name: ",i+1);
      scanf("%s",name);
      printf("Enter marks: ");
      scanf("%d",&marks);
      fprintf(fptr,"\nName: %s \nMarks=%d \n",name,marks);
   }
   fclose(fptr);
   return 0;
}





C program to read the content of a file using fgets()



#include <stdio.h>
#include <stdlib.h>
void main()
{
  FILE *fp;
  char str[80], fname[50];
  printf("Enter the file name:");
  scanf("%s",fname);

  if ((fp= fopen(fname, "r")) == NULL) {
  printf("cannot open file");
  exit(1);
  }

  while(!feof(fp)) {
 fgets(str,79,fp);
 printf("%s",str);
  }

  fclose(fp);
}





Program to read a file and print it content on screen

#include <stdio.h>
#include <stdlib.h>
 
int main()
{
   char ch, file_name[25];
   FILE *fp;
 
   printf("Enter the name of file you wish to see\n");
   gets(file_name);
 
   fp = fopen(file_name,"r"); // read mode
 
   if( fp == NULL )
   {
      perror("Error while opening the file.\n");
      exit(EXIT_FAILURE);
   }
 
   printf("The contents of %s file are :\n", file_name);
 
   while( ( ch = fgetc(fp) ) != EOF )
      printf("%c",ch);
 
   fclose(fp);
   return 0;
}







Program to delete  a file 



#include<stdio.h>
 
main()
{
   int status;
   char file_name[25];
 
   printf("Enter the name of file you wish to delete\n");
   gets(file_name);
 
   status = remove(file_name);
 
   if( status == 0 )
      printf("%s file deleted successfully.\n",file_name);
   else
   {
      printf("Unable to delete the file\n");
      perror("Error");
   }
 
   return 0;
}