foo.c: In function 'main':
foo.c:6:1: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
    6 | scanf("%d%d",&n1,&n2);
      | ^~~~~~~~~~~~~~~~~~~~~
foo.c:7:23: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
    7 | for(int i=0;i<n1;i++){scanf("%d",&a[i]);}
      |                       ^~~~~~~~~~~~~~~~~
foo.c:8:23: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
    8 | for(int i=0;i<n2;i++){scanf("%d",&b[i]);}
      |                       ^~~~~~~~~~~~~~~~~

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