Compilare: user.cpp: In function ‘int main()’: user.cpp:29:10: warning: unused variable ‘ok’ [-Wunused-variable] bool ok = true; ^ user.cpp:53:40: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i < gr[nod].size(); ++i) ^ user.cpp:64:40: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i < gr[vec].size(); ++i) { ^ user.cpp:21:32: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("bal.in", "r", stdin); ^ user.cpp:22:34: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("bal.out", "w", stdout); ^ user.cpp:26:24: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d", &n, &m); ^ user.cpp:28:26: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d", &x, &y); ^