Factorial Calculation Using Recursion in C

This C program calculates the factorial of a given positive integer using a recursive function. The factorial of a number n (denoted as n!) is the product of all positive integers less than or equal to n.

✅ C Program Code:

#include <stdio.h>

int fact(int n)
{       
    if (n == 0 || n == 1)
    {
        return 1;
    }
    else
    {
        return n * fact(n - 1);
    }
}

int main()
{
    int num;
    printf("Enter the number that you want to find factorial:\n");
    scanf("%d", &num);
    if (num < 0)
    {
        printf("Factorial number contain only positive:\n");
    }
    else
    {
        printf("Factorial of a given number %d is %d\n", num, fact(num));
    }
}
  
  
  

📌 How It Works:

• fact(): This is the recursive function that calculates factorial. It returns 1 if n is 0 or 1 (base case). Otherwise, it multiplies n by the factorial of n-1.
• main(): Takes user input for the number and checks if it is negative. If negative, it prints an error message. Otherwise, it calls fact() to calculate factorial and prints the result.

💻 Sample Output:

enter the number that you want to find factorial:
5
Factorial of a given number 5 is 120

🔍 Keywords:

factorial in C, recursive factorial program, factorial using recursion, C programming recursion example, factorial function in C, beginner C programs, recursion in C, factorial calculation