/in/foo.cc: In function 'void dfs(long long int, long long int, int)':
/in/foo.cc:11:14: error: 'dep' was not declared in this scope
     if(sum > dep) return;
              ^~~
/in/foo.cc:22:20: error: 'dep' was not declared in this scope
     long long r = (dep - sum + 1) * b / a;
                    ^~~