foo.c: In function 'main':
foo.c:6:2: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
  scanf("%d",&n);
  ^~~~~~~~~~~~~~
foo.c:10:3: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
  {scanf("%d %d",&b[i],&a[i]);}
   ^~~~~~~~~~~~~~~~~~~~~~~~~~
foo.c:28:19: warning: 'x' may be used uninitialized in this function [-Wmaybe-uninitialized]
      {c[i]=b[i]*(x/a[i]);}
                 ~~^~~~~~

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