Given a number N. The task is to count total numbers under N which are both perfect square and cube of some integers.
Input: N = 100 Output: 2 They are 1 and 64. Input: N = 100000 Output: 6
Approach: For a given positive number N to be a perfect square, it must satisfy P2 = N Similarly, Q3 = N for a perfect cube where P and Q are some positive integers.
N = P2 = Q3
Thus, if N is a 6th power, then this would certainly work. Say N = A6 which can be written as (A3)2 or (A2)3.
So, pick 6th power of every positive integers which are less than equal to N.
Below is the implementation of the above approach:
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