foo.c: In function 'main':
foo.c:56:2: error: expected declaration or statement at end of input
  return 0;
  ^~~~~~
foo.c:11:2: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
  scanf("%d%d", &k1, &k2);
  ^~~~~~~~~~~~~~~~~~~~~~~

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