/in/foo.cc: In function 'int dfs(int, int)':
/in/foo.cc:20:1: warning: no return statement in function returning non-void [-Wreturn-type]
 }
 ^
/in/foo.cc: In function 'int main()':
/in/foo.cc:25:1: warning: this 'for' clause does not guard... [-Wmisleading-indentation]
 for(i=1;i<=n;i++)
 ^~~
/in/foo.cc:32:2: note: ...this statement, but the latter is misleadingly indented as if it is guarded by the 'for'
  for(i=1;i<=n;i++)
  ^~~