foo.c: In function 'main':
foo.c:7:3: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
    7 |  {scanf("%s ",&a[j]);
      |   ^~~~~~~~~~~~~~~~~~
foo.c:8:6: warning: iteration 100 invokes undefined behavior [-Waggressive-loop-optimizations]
    8 |  b[j]=sizeof(a[j]);
      |  ~~~~^~~~~~~~~~~~~
foo.c:6:2: note: within this loop
    6 |  for(j=0;j<=101;j++)
      |  ^~~

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