Compilare: user.cpp: In function ‘int main()’: user.cpp:73:30: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int j=0;j<a.size();j++) ^ user.cpp:90:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(i=0;i<a.size();i++) ///parcurg fiecare dreapta ^ user.cpp:95:31: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while(j<M[i].size()) ^ user.cpp:99:83: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while((M[i][j+1].cx<valoarex||M[i][j+1].cy<valoarey)&&j<M[i].size()) j++; ^ user.cpp:101:32: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if(j<M[i].size()) ^ user.cpp: In function ‘bool cmp(const cercuri&, const cercuri&)’: user.cpp:30:1: warning: control reaches end of non-void function [-Wreturn-type] } ^