/in/foo.cc: In function 'int main()':
/in/foo.cc:28:19: warning: unused variable 'j' [-Wunused-variable]
         int n,e,i,j,x,y,ans;
                   ^
/in/foo.cc:28:25: warning: unused variable 'ans' [-Wunused-variable]
         int n,e,i,j,x,y,ans;
                         ^~~