Today I wanted to challenge myself and try to write a function to determine if an integer is a power of N?
For example:
Input: 1
Output: true
Explanation: 2^0 = 1
Input: 16
Output: true
Explanation: 2^4 = 16
Input: 218
Output: false
Even though the Swift SDK has a built in functionality to accomplish this task, I was eager to challenge my Swift knowledge and see whether I can write this algorithm from scratch?
Could the input values be interpreted in a different way to achieve our objective?
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import Foundation func isPowerOf(n: Int, x: Int ) -> Bool { return ((_abs(x) / n) % n == .zero) } //Could also use default Swift abs() method func _abs( _ n: Int ) -> Int { return n < 0 ? n * -1 : n } //Power Of Two isPowerOf(n: 2, x: 1) //true isPowerOf(n: 2, x: 16) //true isPowerOf(n: 2, x: 8) //true isPowerOf(n: 2, x: 218) //false //Power Of Ten isPowerOf(n: 10, x: 50) //false isPowerOf(n: 10, x: 1500) // true isPowerOf(n: 10, x: 30) //false isPowerOf(n: 10, x: 23) //false |