foo.cc: In function 'int main()':
foo.cc:17:26: warning: iteration 9 invokes undefined behavior [-Waggressive-loop-optimizations]
   17 |                 if(b>=a[j]) aum++;
      |                       ~~~^
foo.cc:15:22: note: within this loop
   15 |         for(int j=1;j<=10;j++)
      |                     ~^~~~

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