foo.cc: In function 'int main()':
foo.cc:26:23: error: 'num' was not declared in this scope; did you mean 'enum'?
   26 |  pre[n]=1,now=n,cnt=n,num=0;
      |                       ^~~
      |                       enum

正在同步测试数据，请稍后
Found 10 testcases.
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