foo.c: In function 'main':
foo.c:5:5: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
     scanf("%d",&a);
     ^~~~~~~~~~~~~~
foo.c:9:4: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
    scanf("%d",&b[i]);
    ^~~~~~~~~~~~~~~~~

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