foo.cc: In function 'int dfs2(int)':
foo.cc:53:1: warning: no return statement in function returning non-void [-Wreturn-type]
   53 | }
      | ^
foo.cc: In function 'int main()':
foo.cc:86:9: warning: this 'else' clause does not guard... [-Wmisleading-indentation]
   86 |         else de=maxn/2;maxn=0;
      |         ^~~~
foo.cc:86:24: note: ...this statement, but the latter is misleadingly indented as if it were guarded by the 'else'
   86 |         else de=maxn/2;maxn=0;
      |                        ^~~~
foo.cc: In function 'int dfs(int, int)':
foo.cc:43:1: warning: control reaches end of non-void function [-Wreturn-type]
   43 | }
      | ^

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