Compilare: user.cpp: In function ‘void dfs(int)’: user.cpp:24:26: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (i=0;i<v[x].size();i++) { ^ user.cpp: In function ‘void rmq()’: user.cpp:37:13: warning: unused variable ‘x’ [-Wunused-variable] int i,j,x,y,a,b; ^ user.cpp:37:15: warning: unused variable ‘y’ [-Wunused-variable] int i,j,x,y,a,b; ^ user.cpp: In function ‘int main()’: user.cpp:97:11: warning: unused variable ‘j’ [-Wunused-variable] int i,j,x,y,op,a,b,c; ^ user.cpp: In function ‘int get_node(int, int, int, int)’: user.cpp:93:1: warning: control reaches end of non-void function [-Wreturn-type] } ^