Compilare: user.cpp: In function ‘void dfs(int)’: user.cpp:25:26: 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:35:13: warning: unused variable ‘k’ [-Wunused-variable] int i,j,k,t,r,x,y; ^ user.cpp:35:15: warning: unused variable ‘t’ [-Wunused-variable] int i,j,k,t,r,x,y; ^ user.cpp:35:17: warning: unused variable ‘r’ [-Wunused-variable] int i,j,k,t,r,x,y; ^