Compilare: main.cpp: In function 'int hamilton(int, int)': main.cpp:20:12: warning: suggest parentheses around comparison in operand of '&' [-Wparentheses] if (mask != 1 & k == 0) ~~~~~^~~~ main.cpp: In function 'int main()': main.cpp:36:37: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("hamilton.in", "r", stdin); ^ main.cpp:37:39: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("hamilton.out", "w", stdout); ^ main.cpp:39:24: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d", &N, &M); ^ main.cpp:43:39: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d%d", &from, &to, &cost); ^