Compilare: user.cpp: In function ‘void add(int, int)’: user.cpp:37:36: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0; i < graph[x].size(); ++i) ^ user.cpp: In function ‘int main()’: user.cpp:85:30: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0; i < gv.size(); ++i){ ^ user.cpp:93:32: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int j = i; j < gv.size(); ++j){ ^ user.cpp:95:27: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if(j != gv.size() - 1) ^