foo.cc:3:23: error: expected unqualified-id before ';' token
 int x[30005],y[30005],;
                       ^
foo.cc: In function 'int main()':
foo.cc:6:7: error: 'a' was not declared in this scope
  cin>>a>>b;
       ^
foo.cc:6:10: error: 'b' was not declared in this scope
  cin>>a>>b;
          ^

正在同步测试数据，请稍后
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