foo.c: In function 'main':
foo.c:33:12: warning: unused variable 'i' [-Wunused-variable]
   33 |  int x, y, i;
      |            ^
foo.c: In function 'gbs':
foo.c:30:1: warning: control reaches end of non-void function [-Wreturn-type]
   30 | }
      | ^
foo.c: In function 'main':
foo.c:34:2: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
   34 |  scanf("%d%d", &x, &y);
      |  ^~~~~~~~~~~~~~~~~~~~~

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