Given a positive number k, we need to find a minimum value of positive integer n, such that XOR of n and n+1 is equal to k. If no such n exist then print -1.
Example 1:
Input: k = 3
Output: 1
Explaination: 1 xor 2 = 3.
Example 2:
Input: k = 6
Output: -1
Explaination: There is no such n, so that,
n xor n+1 = k.
Your Task:
You do not need to read input or print anything. Your task is to complete the function xorCal() which takes k as input parameter and returns the value of n. If there is no such , then it returns -1.
Expected Time Complexity: O(1)
Expected Auxiliary Space: O(1)
Constraints:
1 ≤ k ≤ 100

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