Write a C program to calculate factorial of a number using recursion.

Program:-

#include <stdio.h>
mul(int n);
int main()
{
    int n;
    printf("Enter a positive integer: ");
    scanf("%d", &n);
    printf("Factorial of %d = %ld", n, mul(n));
    return 0;
}
mul(int n)
{
    if (n >= 1)
        return n*mul(n-1);
    else
        return 1;

}


Output:-

Write a C program Using user-defined function for addition of N numbers.
Program:-
#include <stdio.h>
int addNumbers(int n);
int main()
{
    int num;
    printf("Enter a positive integer: ");
    scanf("%d", &num);
    printf("Sum = %d",add(num));
    return 0;
}
int add(int n)
{
    if(n != 0)
        return n + add(n-1);
    else
        return n;
}

Output:-

Write a C Program to perform addition of two matrices.

Program:-

#include <stdio.h>
void 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");
   }

}


Output:-

Write a C Program to read array of integers and print its sum and average.

Program:-
#include <stdio.h>
void main()
{
    int Arr[100], n, i, sum = 0;

    printf("Enter the number of elements : ");
    scanf("%d", &n);

    for (i = 0; i < n; i++)
    {
        printf("Enter element %d : ", i + 1);
        scanf("%d", &Arr[i]);
        sum += Arr[i];
    }
    printf("\nThe sum of the array is : %d", sum);
    printf("\nThe average of the array is : %0.2f", (float)sum / n);
}

Output:-

Program:- Write a C Program To print the given pattern.
1
22
333
4444

Program:-

1. #include <stdio.h>
2.  
3. void main() {
4. for(int i = 1; i < 5; i++) {
5. for(int j = 0; j < i; j++) {
6. printf("%d", i);
7. }
8. printf("\n");
9. }
10. }

Output:-

1. 
   

1
22
333
44444

Program:-

Program:-

#include <stdio.h> 
void main() 
{ 
    int n, i, a = 1; 
    printf("Enter a number: \n"); 
    scanf("%d", &n); 
    for (i = 2; i <= n / 2; i++) { 
        if (n % i == 0) { 
            a = 0; 
            break; 
        } 
    } 
    if (a == 1) { 
        printf("%d is a prime number", n); 
    } 
    else { 
        printf("%d is not a prime number", n); 
    } 

}


Output:-

Program:-

#include <stdio.h>
void main()
{
    char a;
    int isLowercaseVowel, isUppercaseVowel;
    printf("Enter an alphabet: ");
    scanf("%c",&a);
if(a == 'a'|| a == 'e' || a == 'i' || a == 'o' || a == 'u' || a == 'A' || a == 'E' || a == 'I' || a == 'O' || a == 'U' )
{
   printf(" vowel.",&a); 
}
 else
 {
        printf("not vowel",&a); 
 }

}

Output:-

Program:-

#include <stdio.h>
void main()
{
    double a,b,c;

    printf("Enter three different numbers: ");
    scanf("%lf %lf %lf", &a,&b,&c);

    if( a>=b && a>=c )
        printf("%.2f is the largest number.", a);

    if( b>=a && b>=c )
        printf("%.2f is the largest number.", b);

    if( c>=a && c>=b )
        printf("%.2f is the largest number.", c);
  

}

Output:-

Program:-

#include <stdio.h>
void main()
{
    double a;

    printf("Enter a number: ");
    scanf("%lf", &a);
    if (a < 0.0)
        printf("You entered number is negative number.");
    else if (a > 0.0)
        printf("You entered number is  positive number.");
    else
        printf("You entered number is Zero number.");


}

Output:-

Program:-

#include <stdio.h>
void main()
{
    int y;
    printf("Enter year : ");
    scanf("%d", &y);
    if(y%4==0)
    {
        printf("This is leap year ");
    }
    else
    {
        printf("This is not leap year");
    }


}

OutPut:-

Program:-

#include <stdio.h>
void main()
{
  int a,b,c;
  printf("Enter two integers\n");
  scanf("%d%d", &a, &b);
  printf("Before Swapping\nA = %d\nB = %d\n", a,b);
  c = a;
  a = b;
  b = c;
  printf("After Swapping\nA = %d\nB = %d\n", a,b);

}
Output:-

Program:-

#include <stdio.h> 
int main()
{
int r;
float a;
printf("enter radius of the circle: ");
scanf("%d",&r);
a=(3.14*r*r)/7;
printf("area of circle is: %f\n",a);


}


Output:-

Program:-

#include <stdio.h>

void main()
{
   int a, b, add, sub, mul;
   float divi;

   printf("Enter two integers\n");
   scanf("%d%d", &a, &b);

   add = a + b;
   sub = a - b;
   mul = a * b;
   divi = a / (float)b;   

   printf("Addition = %d\n", add);
   printf("subtraction = %d\n", sub);
   printf("Multiplication = %d\n", mul);
   printf("Division = %.2f\n", divi);


}


Output:-