foo.c: In function 'main':
foo.c:16:7: warning: suggest explicit braces to avoid ambiguous 'else' [-Wdangling-else]
     if(a[i%na]==0)
       ^
foo.c:19:7: warning: suggest explicit braces to avoid ambiguous 'else' [-Wdangling-else]
     if(a[i%na]==1)
       ^
foo.c:22:7: warning: suggest explicit braces to avoid ambiguous 'else' [-Wdangling-else]
     if(a[i%na]==2)
       ^
foo.c:25:7: warning: suggest explicit braces to avoid ambiguous 'else' [-Wdangling-else]
     if(a[i%na]==3)
       ^
foo.c:28:7: warning: suggest explicit braces to avoid ambiguous 'else' [-Wdangling-else]
     if(a[i%na]==4)
       ^
foo.c:6:2: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
  scanf("%d%d%d",&n,&na,&nb);
  ^~~~~~~~~~~~~~~~~~~~~~~~~~
foo.c:9:3: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
   scanf("%d",&a[i]);
   ^~~~~~~~~~~~~~~~~
foo.c:11:3: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
   scanf("%d",&b[i]);
   ^~~~~~~~~~~~~~~~~

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