foo.c: In function 'input':
foo.c:6:3: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
    6 |   scanf("%d",&a[i]);
      |   ^~~~~~~~~~~~~~~~~
foo.c: In function 'main':
foo.c:41:2: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
   41 |  scanf("%d %d",&n1 ,&n2);
      |  ^~~~~~~~~~~~~~~~~~~~~~~
foo.c: In function 'FindSecondMax':
foo.c:28:15: warning: 'l' may be used uninitialized in this function [-Wmaybe-uninitialized]
   28 |       second=a[l-1];
      |               ^

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