foo.c: In function 'main':
foo.c:7:2: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
    7 |  scanf("%d", &n);
      |  ^~~~~~~~~~~~~~~
foo.c:12:3: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
   12 |   scanf("%d", &a[i]);
      |   ^~~~~~~~~~~~~~~~~~
foo.c:23:5: warning: 'y[0]' may be used uninitialized in this function [-Wmaybe-uninitialized]
   23 |  max=y[0];
      |  ~~~^~~~~

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