foo.c: In function 'main':
foo.c:5:2: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
  scanf("%d%d",&n1,&n2);
  ^~~~~~~~~~~~~~~~~~~~~
foo.c:7:3: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
   scanf("%d",&a1[i]);
   ^~~~~~~~~~~~~~~~~~
foo.c:9:3: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
   scanf("%d",&a2[j]);
   ^~~~~~~~~~~~~~~~~~
foo.c: In function 'Unique':
foo.c:33:3: warning: 'c[0]' may be used uninitialized in this function [-Wmaybe-uninitialized]
   printf("%d ",c[m]);
   ^~~~~~~~~~~~~~~~~~

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