Compilare: user.cpp: In function ‘void read()’: user.cpp:17:8: warning: unused variable ‘j’ [-Wunused-variable] int i,j,x,y; ^ user.cpp: In function ‘void dfs(int, int, int)’: user.cpp:33:31: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i=0;i<vec[nod].size();++i) ^ user.cpp: In function ‘void write()’: user.cpp:77:36: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (j=0;j<sol[i].size();++j) ^