foo.c: In function 'Merge':
foo.c:22:8: warning: unused variable 'x' [-Wunused-variable]
   22 |  int i,x,j,k,flag;
      |        ^
foo.c: In function 'main':
foo.c:8:2: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
    8 |  scanf("%d%d%d",&n1,&n2,&n3);
      |  ^~~~~~~~~~~~~~~~~~~~~~~~~~~
foo.c:10:2: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
   10 |  scanf("%d",&a1[i]);
      |  ^~~~~~~~~~~~~~~~~~
foo.c:12:2: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
   12 |  scanf("%d",&a2[i]);
      |  ^~~~~~~~~~~~~~~~~~
foo.c:14:2: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
   14 |  scanf("%d",&a3[i]);
      |  ^~~~~~~~~~~~~~~~~~

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