foo.c: In function 'main':
foo.c:7:2: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
  scanf("%d",&n);
  ^~~~~~~~~~~~~~
foo.c:9:19: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
  for(i=0;i<n;i++) scanf("%d",&m[i]);
                   ^~~~~~~~~~~~~~~~~
foo.c:10:2: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
  scanf("%d %d",&a,&b);
  ^~~~~~~~~~~~~~~~~~~~

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