foo.c: In function 'fun':
foo.c:7:3: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
    7 |   scanf("%d",&a[i]);
      |   ^~~~~~~~~~~~~~~~~
foo.c: In function 'main':
foo.c:36:2: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
   36 |  scanf("%d %d",&n1,&n2);
      |  ^~~~~~~~~~~~~~~~~~~~~~
foo.c: In function 'FindiSecondMax':
foo.c:31:9: warning: 'r2' may be used uninitialized in this function [-Wmaybe-uninitialized]
   31 |  return r2;
      |         ^~
foo.c:25:15: warning: 'r1' may be used uninitialized in this function [-Wmaybe-uninitialized]
   25 |   if(a[i]>max2&&i!=r1)
      |      ~~~~~~~~~^~~~~~~

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