foo.c: In function 'main':
foo.c:6:2: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
    6 |  scanf("%d",&n);
      |  ^~~~~~~~~~~~~~
foo.c:9:3: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
    9 |   scanf("%d",&a[i]);
      |   ^~~~~~~~~~~~~~~~~
foo.c:26:7: warning: 'r' may be used uninitialized in this function [-Wmaybe-uninitialized]
   26 |  while(r!=0)
      |       ^
foo.c:21:6: note: 'r' was declared here
   21 |  int r,t;
      |      ^
foo.c: In function 'max':
foo.c:26:7: warning: 'r' may be used uninitialized in this function [-Wmaybe-uninitialized]
   26 |  while(r!=0)
      |       ^

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