Example: Factorial Calculation in C

C
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Java
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// Factorial Calculation
#include <stdio.h>

long long factorial(int n) {
    // Step 1: Define the base case
    // The factorial of 0 or 1 is 1.
    if (n == 0 || n == 1) {
        return 1;
    }
    // Step 2: Define the recursive step
    // n! = n * (n-1)!
    return n * factorial(n - 1);
}

int main() {
    // Step 1: Declare a variable for the number
    int num = 5;
    // Step 2: Call the recursive factorial function
    long long result = factorial(num);
    // Step 3: Print the result
    printf("Factorial of %d is %lld\n", num, result);
    return 0;
}