Compilare: user.cpp: In function ‘void dfs(int, int)’: user.cpp:26:26: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (i=0;i<v[x].size();i++) { ^ user.cpp: In function ‘int lcaquery(int, int)’: user.cpp:36:9: warning: unused variable ‘i’ [-Wunused-variable] int i,j,a1,b1; ^ user.cpp:36:11: warning: unused variable ‘j’ [-Wunused-variable] int i,j,a1,b1; ^ user.cpp: In function ‘int main()’: user.cpp:70:11: warning: unused variable ‘j’ [-Wunused-variable] int i,j,x,y,val; ^