foo.cc:7:6: error: expected initializer before 'a'
    7 | node a[400005];
      |      ^
foo.cc: In function 'int main()':
foo.cc:24:9: error: 'a' was not declared in this scope
   24 |    cin>>a[i].wz;
      |         ^
foo.cc:29:9: error: 'a' was not declared in this scope
   29 |    cin>>a[i].jz;
      |         ^
foo.cc:32:8: error: 'a' was not declared in this scope
   32 |   sort(a,a+2*n,cmp);
      |        ^
foo.cc:16:9: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result]
   16 |  freopen("gem.in","r",stdin);
      |  ~~~~~~~^~~~~~~~~~~~~~~~~~~~
foo.cc:17:9: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result]
   17 |  freopen("gem.out","w",stdout);
      |  ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~

Found 10 testcases.
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