#include <stdio.h>
 
int main() {
    int n;
    long long factorial = 1;  // Use long long for larger factorial values
 
    printf("Enter a number (n): ");
    scanf("%d", &n);
 
    if (n < 0) {
        printf("Factorial is not defined for negative numbers.\n");
    } else {
        for (int i = 1; i <= n; ++i) {
            factorial *= i;  // Multiply factorial by i in each iteration
        }
        printf("%d! is %lld.\n", n, factorial);
    }
 
    return 0;
}

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