Compilare: user.cpp: In function ‘int main()’: user.cpp:72:31: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(i = 1; i < cycle.size(); ++ i) { ^ user.cpp:35:37: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("domino.in", "r", stdin); ^ user.cpp:36:39: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("domino.out", "w", stdout); ^ user.cpp:39:20: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &n); ^ user.cpp:41:30: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d", &a, &b); ^