/in/foo.cc: In function 'int dfs(int, int)':
/in/foo.cc:11:10: warning: unused variable 'res1' [-Wunused-variable]
  int x,y,res1=0,res2=0;
          ^~~~
/in/foo.cc:11:17: warning: unused variable 'res2' [-Wunused-variable]
  int x,y,res1=0,res2=0;
                 ^~~~