package LeetCode_658
/**
* 658. Find K Closest Elements
* https://leetcode.com/problems/find-k-closest-elements/description/
*
* Given a sorted array arr, two integers k and x, find the k closest elements to x in the array.
* The result should also be sorted in ascending order.
* If there is a tie, the smaller elements are always preferred.
Example 1:
Input: arr = [1,2,3,4,5], k = 4, x = 3
Output: [1,2,3,4]
Example 2:
Input: arr = [1,2,3,4,5], k = 4, x = -1
Output: [1,2,3,4]
Constraints:
1 <= k <= arr.length
1 <= arr.length <= 10^4
Absolute value of elements in the array and x will not exceed 104
* */
class Solution {
/*
* solution: compare arr[0], arr[lastIndex] with x every time, delete the number that have a large distance,
* Time complexity:O(n), Space complexity:O(1)
* */
fun findClosestElements(arr: IntArray, k: Int, x: Int): List<Int> {
var list = arr.toList()
while (list.size > k) {
//if the distance of last element larger than the first one, delete the last element,
//otherwise delete the first one
if (x - list[0] <= list[list.size - 1] - x) {
//Returns a list containing all elements except last [n] elements.
//remove from tail
list = list.dropLast(1)
} else {
//Returns a list containing all elements except first [n] elements.
list = list.drop(1)
}
}
return list
}
}
