Compilare: user.cpp: In function ‘void BuildFG()’: user.cpp:40:38: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int j = 0; j < G[i].size(); ++ j) ^ user.cpp:45:38: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int j = 0; j < G[i].size(); ++ j) ^ user.cpp: In function ‘void AssociateColors()’: user.cpp:94:43: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0; i < ColoringOrder.size(); ++ i) ^ user.cpp: In function ‘int main()’: user.cpp:112:43: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("nowhere-zero.in", "r", stdin); ^ user.cpp:113:45: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("nowhere-zero.out", "w", stdout); ^ user.cpp:115:27: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%i %i", &N, &M); ^ user.cpp:116:64: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] for(int i = 1; i <= N; ++ i) scanf("%lf %lf", &X[i], &Y[i]); ^ user.cpp:119:31: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%i %i", &A, &B); ^