foo.c:48:2: error: expected identifier or '(' before 'return'
  return n;
  ^~~~~~
foo.c:49:1: error: expected identifier or '(' before '}' token
 }
 ^
foo.c: In function 'main':
foo.c:14:2: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
  scanf("%d %d", &n1, &n2);
  ^~~~~~~~~~~~~~~~~~~~~~~~
foo.c:18:3: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
   scanf("%d", &a[i]);
   ^~~~~~~~~~~~~~~~~~
foo.c:21:3: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
   scanf("%d", &b[i]);
   ^~~~~~~~~~~~~~~~~~
foo.c: In function 'Unique':
foo.c:47:2: warning: control reaches end of non-void function [-Wreturn-type]
  }
  ^

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