foo.c:6:7: warning: return type of 'main' is not 'int' [-Wmain]
 }void main()
       ^~~~
foo.c: In function 'main':
foo.c:7:8: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
 {int n;scanf("%d",&n);
        ^~~~~~~~~~~~~~

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