Not passijng in codechef

it is the same quesion of question. however on submitting on hackerblocks it is showing correct answer whereas on submitting on codechef it is passing 15/20 test cases. please tell what am i missing

May be due to some corner test cases, for which your code doesnot give correct output and those test cases were not in hackerblock back-end.
Please analyze your approach again.

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