foo.cc: In function 'int main()':
foo.cc:10:7: warning: iteration 7 invokes undefined behavior [-Waggressive-loop-optimizations]
   10 |   a[i]=i;
      |   ~~~~^~
foo.cc:8:15: note: within this loop
    8 |  for(int i=0;i<49;i++)
      |              ~^~~
foo.cc:14:14: warning: iteration 1 invokes undefined behavior [-Waggressive-loop-optimizations]
   14 |   b[j]=a[temp];
      |        ~~~~~~^
foo.cc:12:15: note: within this loop
   12 |  for(int j=0;j<7;j++)
      |              ~^~

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