[LeetCode/Kotlin]Easy - 169. Majority Element

Majority Element - LeetCode

문제

Given an array nums of size n, return the majority element.

The majority element is the element that appears more than ⌊n / 2⌋ times. You may assume that the majority element always exists in the array.

Example 1:

Input: nums = [3,2,3]
Output: 3

Example 2:

Input: nums = [2,2,1,1,1,2,2]
Output: 2

Constraints:

• n == nums.length
• 1 <= n <= 5 * 104
• 109 <= nums[i] <= 109

Follow-up:

Could you solve the problem in linear time and in

O(1)

space?

풀이

나의 풀이법

풀이 접근 과정

nums를 오름차순 정렬한 후 각 숫자의 cnt를 갱신했다.

최종 소스코드

class Solution {
    fun majorityElement(nums: IntArray): Int {
        nums.sort()
        var maxCount = 0
        var cnt = 0
        var before = nums[0]
        var answer = nums[0]
        nums.forEach {
            if (before != it) {
                if (maxCount < cnt) {
                    maxCount = cnt
                    answer = before
                }
                cnt = 1
                before = it
            } else cnt++
        }

        if (maxCount < cnt) return before
        else return answer
    }
}