Compilare: user.cpp: In function ‘bool PairUp(int)’: user.cpp:18:37: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0; i < G[Node].size(); ++ i) ^ user.cpp:29:37: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0; i < G[Node].size(); ++ i) ^ user.cpp: In function ‘int main()’: user.cpp:62:37: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("cuplaj.in", "r", stdin); ^ user.cpp:63:39: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("cuplaj.out", "w", stdout); ^ user.cpp:65:34: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%i %i %i", &N, &M, &E); ^ user.cpp:68:31: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%i %i", &A, &B); ^