Given a number “n”, find its total number of divisors are even or odd.
Input : n = 10 Output : Even Input: n = 100 Output: Odd Input: n = 125 Output: Even
A naive approach would be to find all the divisors and then see if the total number of divisors is even or odd.
Time complexity for such a solution would be O(sqrt(n))
The count of divisor: Even
We can observe that the number of divisors is odd only in case of perfect squares. Hence the best solution would be to check if the given number is perfect square or not. If it\’s a perfect square, then the number of divisors would be odd, else it\’d be even.
The count of divisorof 10 is: Even
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