foo.c: In function 'main':
foo.c:6:8: warning: too many arguments for format [-Wformat-extra-args]
    6 |  scanf("%d", &a, &b);
      |        ^~~~
foo.c:6:2: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
    6 |  scanf("%d", &a, &b);
      |  ^~~~~~~~~~~~~~~~~~~

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