Compilare: user.cpp: In function ‘void tarjan(int)’: user.cpp:21:25: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(i=0;i<gr[nod].size();i++) ^ user.cpp:15:8: warning: unused variable ‘j’ [-Wunused-variable] int i,j; ^ user.cpp: In function ‘int main()’: user.cpp:74:21: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(i=0;i<scc.size();i++) ^ user.cpp:76:25: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(j=0;j<scc[i].size();j++) ^ user.cpp:55:14: warning: unused variable ‘z’ [-Wunused-variable] int i,j,x,y,z; ^