foo.cc:8:1: error: expected ',' or ';' before 'void'
    8 | void dfs(int u,int cnt)
      | ^~~~
foo.cc: In function 'int main()':
foo.cc:25:9: error: 'dfs' was not declared in this scope; did you mean 'ffs'?
   25 |         dfs(0,0);
      |         ^~~
      |         ffs

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