Compilare: user.cpp: In function ‘void buildPairs()’: user.cpp:43:38: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int j = 0; j < G[i].size(); j++) ^ user.cpp:49:38: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int j = 0; j < G[i].size(); j++) ^ user.cpp:51:17: warning: unused variable ‘neighb’ [-Wunused-variable] int neighb = G[i][j].first, c = G[i][j].second; ^ user.cpp: In function ‘void Solve()’: user.cpp:135:29: warning: variable ‘second’ set but not used [-Wunused-but-set-variable] int last = 1,last2 = 0, second; ^ user.cpp: In function ‘int main()’: user.cpp:156:37: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("ulei.out", "w", stdout); ^