foo.c: In function 'main':
foo.c:36:2: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
  scanf("%d %d",&n1,&n2);
  ^~~~~~~~~~~~~~~~~~~~~~
foo.c:39:3: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
   scanf("%d",&a[i]);
   ^~~~~~~~~~~~~~~~~
foo.c:44:3: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
   scanf("%d",&b[i]);
   ^~~~~~~~~~~~~~~~~
foo.c:79:9: warning: 'cnt2' may be used uninitialized in this function [-Wmaybe-uninitialized]
     cnt2++;
     ~~~~^~
foo.c:63:9: warning: 'cnt1' may be used uninitialized in this function [-Wmaybe-uninitialized]
     cnt1++;
     ~~~~^~

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