foo.c:15:6: warning: return type of 'main' is not 'int' [-Wmain]
   15 | void main()
      |      ^~~~
foo.c: In function 'main':
foo.c:21:4: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
   21 |    scanf("%d",&j[i]);
      |    ^~~~~~~~~~~~~~~~~
foo.c:22:3: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
   22 |   scanf("%d",&x);
      |   ^~~~~~~~~~~~~~

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