foo.c: In function 'main':
foo.c:6:2: error: expected ',' or ';' before 'scanf'
  scanf("%d", &a);
  ^~~~~
foo.c:17:2: error: expected ';' before '}' token
  }
  ^
foo.c:21:2: error: expected ';' before '}' token
  }
  ^

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