foo.cc: In function 'int main()':
foo.cc:20:23: warning: iteration 99999 invokes undefined behavior [-Waggressive-loop-optimizations]
   20 |                 if(a[i])
      |                    ~~~^
foo.cc:19:22: note: within this loop
   19 |         for(int i=1;i<=100000;i++)
      |                     ~^~~~~~~~

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