foo.c: In function 'input':
foo.c:4:18: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
    4 |  for(i=0;i<n;i++)scanf("%d",&a[i]);}
      |                  ^~~~~~~~~~~~~~~~~
foo.c: In function 'main':
foo.c:19:2: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
   19 |  scanf("%d %d",&n1 ,&n2);
      |  ^~~~~~~~~~~~~~~~~~~~~~~
foo.c: In function 'FindSecondMax':
foo.c:13:28: warning: 'l' may be used uninitialized in this function [-Wmaybe-uninitialized]
   13 |   { if(second==max)second=a[l-1];
      |                            ^

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