Compilare: user.cpp: In function ‘void flip(int, int)’: user.cpp:51:27: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(i = 0; i < G[x].size(); i++) ^ user.cpp: In function ‘int main()’: user.cpp:59:34: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("meciul.in", "r", stdin); ^ user.cpp:60:36: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("meciul.out", "w", stdout); ^ user.cpp:62:28: warning: ignoring return value of ‘size_t fread(void*, size_t, size_t, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] fread(Buf, 1, MaxB, stdin); ^ user.cpp: In function ‘int GetInt()’: user.cpp:24:39: warning: ignoring return value of ‘size_t fread(void*, size_t, size_t, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] fread(Buf, 1, MaxB, stdin), Ptr = 0; ^ user.cpp:28:39: warning: ignoring return value of ‘size_t fread(void*, size_t, size_t, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] fread(Buf, 1, MaxB, stdin), Ptr = 0; ^