foo.cc: In function 'int main()':
foo.cc:10:12: warning: iteration 10003 invokes undefined behavior [-Waggressive-loop-optimizations]
   10 |   if(!vis[i])
      |       ~~~~~^
foo.cc:8:16: note: within this loop
    8 |  for(int i=2; i<=10005; i++)
      |               ~^~~~~~~

Found 10 testcases.
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