Compilare: user.cpp: In function ‘void BF()’: user.cpp:16:31: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (i=0; i<v[k].size(); ++i) ^ user.cpp: In function ‘void NUMARA()’: user.cpp:30:31: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (i=0; i<v[k].size(); ++i) ^ user.cpp: In function ‘int main()’: user.cpp:43:36: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen ("graf.in", "r", stdin); ^ user.cpp:44:38: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen ("graf.out", "w", stdout); ^ user.cpp:45:39: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf ("%d%d%d%d", &n, &m, &X, &Y); ^ user.cpp:48:31: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf ("%d%d", &x, &y); ^