#!/usr/bin/env python3
"""Simple verification script - computes factorial and outputs result."""
import sys

def factorial(n):
    if n <= 1:
        return 1
    return n * factorial(n - 1)

if __name__ == "__main__":
    n = int(sys.argv[1]) if len(sys.argv) > 1 else 5
    result = factorial(n)
    print(f"factorial({n}) = {result}")