foo.c: In function 'main':
foo.c:7:4: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
    7 |  { scanf("%c",&a[i]);
      |    ^~~~~~~~~~~~~~~~~
foo.c:10:3: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
   10 |   scanf("%d %d",&n,&m);
      |   ^~~~~~~~~~~~~~~~~~~~

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