foo.c: In function 'main':
foo.c:7:2: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
    7 |  scanf("%d%d",&L,&M);
      |  ^~~~~~~~~~~~~~~~~~~
foo.c:11:3: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
   11 |   scanf("%d%d",&beg,&end);
      |   ^~~~~~~~~~~~~~~~~~~~~~~

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