foo.c: In function 'main':
foo.c:5:10: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
 int n,i; scanf("%d", &n);
          ^~~~~~~~~~~~~~~
foo.c:6:12: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
  int x, y; scanf("%d", &x);
            ^~~~~~~~~~~~~~~
foo.c:13:4: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
    scanf("%d", &y);
    ^~~~~~~~~~~~~~~

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