foo.c: In function 'primecount':
foo.c:24:8: warning: unused variable 'x' [-Wunused-variable]
   24 |  int i,x,m=0,j,flag;
      |        ^
foo.c: In function 'main':
foo.c:6:5: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
    6 |     scanf("%d%d",&n1,&n2);
      |     ^~~~~~~~~~~~~~~~~~~~~
foo.c:11:6: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
   11 |      scanf("%d",&a[i]);
      |      ^~~~~~~~~~~~~~~~~
foo.c:15:3: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
   15 |   scanf("%d",&b[j]);
      |   ^~~~~~~~~~~~~~~~~

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