Compilare: user.cpp: In function ‘void addFriends()’: user.cpp:42:38: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int j = 0; j < G[i].size(); j++) ^ user.cpp:45:47: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int k = 0; k < G[neighb].size(); k++) ^ user.cpp: In function ‘void addEdge(int, int)’: user.cpp:56:34: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0; i < G[y].size(); i++) ^ user.cpp:61:35: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0; i < GT[x].size(); i++) ^ user.cpp: In function ‘void eraseEdge(int, int)’: user.cpp:73:34: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0; i < G[y].size(); i++) ^ user.cpp:78:35: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0; i < GT[x].size(); i++) ^ user.cpp: In function ‘int main()’: user.cpp:154:41: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("prietene.out", "w", stdout); ^