#include <stdio.h> // Returns 1 if n is even, and 0 if not int isEven(int n) { return n % 2 != 1; // The buggy check } void test(int n, int expected) { int result = isEven(n); if (result == expected) { printf("PASS: %d\n", n); } else { printf("FAIL: %d (expected %d, got %d)\n", n, expected, result); } } int main() { test(7, 0); test(4, 1); test(0, 1); test(-7, 0); return 0; }