foo.c:13:1: error: expected identifier or '(' before '}' token
   13 | }
      | ^
foo.c: In function 'main':
foo.c:5:2: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
    5 |  scanf("%d%d",&a,&b);
      |  ^~~~~~~~~~~~~~~~~~~

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