LeetCode in Kotlin

1558. Minimum Numbers of Function Calls to Make Target Array

Medium

You are given an integer array nums. You have an integer array arr of the same length with all values set to 0 initially. You also have the following modify function:

You want to use the modify function to covert arr to nums using the minimum number of calls.

Return the minimum number of function calls to make nums from arr.

The test cases are generated so that the answer fits in a 32-bit signed integer.

Example 1:

Input: nums = [1,5]

Output: 5

Explanation: Increment by 1 (second element): [0, 0] to get [0, 1] (1 operation).

Double all the elements: [0, 1] -> [0, 2] -> [0, 4] (2 operations).

Increment by 1 (both elements) [0, 4] -> [1, 4] -> [1, 5] (2 operations).

Total of operations: 1 + 2 + 2 = 5.

Example 2:

Input: nums = [2,2]

Output: 3

Explanation: Increment by 1 (both elements) [0, 0] -> [0, 1] -> [1, 1] (2 operations).

Double all the elements: [1, 1] -> [2, 2] (1 operation).

Total of operations: 2 + 1 = 3.

Example 3:

Input: nums = [4,2,5]

Output: 6

Explanation: (initial)[0,0,0] -> [1,0,0] -> [1,0,1] -> [2,0,2] -> [2,1,2] -> [4,2,4] -> [4,2,5](nums).

Constraints:

Solution

class Solution {
    fun minOperations(nums: IntArray): Int {
        var ops = 0
        for (bit in 0..31) {
            var nonzero = false
            for (i in nums.indices) {
                ops += nums[i] % 2
                nums[i] /= 2
                nonzero = nonzero or (nums[i] > 0)
            }
            if (nonzero) {
                ops++
            } else {
                break
            }
        }
        return ops
    }
}