foo.c: In function 'main':
foo.c:21:15: warning: variable 'm2' set but not used [-Wunused-but-set-variable]
   21 |  int n1,n2,m1,m2;
      |               ^~
foo.c:21:12: warning: variable 'm1' set but not used [-Wunused-but-set-variable]
   21 |  int n1,n2,m1,m2;
      |            ^~
foo.c:22:2: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
   22 |  scanf("%d%d",&n1,&n2);
      |  ^~~~~~~~~~~~~~~~~~~~~
foo.c:25:3: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
   25 |   scanf("%d",&a[i]);
      |   ^~~~~~~~~~~~~~~~~
foo.c:29:3: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
   29 |   scanf("%d",&b[i]);
      |   ^~~~~~~~~~~~~~~~~

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