Compilare: user.cpp: In function ‘void dfs(int, int)’: user.cpp:15:26: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (i=0;i<v[x].size();i++) { ^ user.cpp: In function ‘void color(int)’: user.cpp:29:26: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (i=0;i<v[x].size();i++) { ^ user.cpp: In function ‘int main()’: user.cpp:39:11: warning: unused variable ‘j’ [-Wunused-variable] int i,j,x,y; ^