foo.c: In function 'main':
foo.c:6:8: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
    6 |  int n;scanf("%d",&n);
      |        ^~~~~~~~~~~~~~
foo.c:8:3: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
    8 |   scanf("%d",&a[i]);
      |   ^~~~~~~~~~~~~~~~~
foo.c:12:6: warning: 'b[0]' may be used uninitialized in this function [-Wmaybe-uninitialized]
   12 |  int max=b[0];
      |      ^~~

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