Write a function that returns true if k^k == n for input (n, k) and return false otherwise.
kToK(4, 2) ➞ true
kToK(387420489, 9) ➞ true
// 9^9 == 387420489
kToK(3124, 5) ➞ false
kToK(17, 3) ➞ false
The ^ operator refers to exponentiation operation, not the bitwise XOR operation.