Sort Transformed Array

Posted 2020-07-30 keepshuatishuati

 1 public class Solution {
 2     public int[] sortTransformedArray(int[] nums, int a, int b, int c) {
 3         if (nums.length < 2) {
 4             return nums;
 5         }
 6         int[] result = new int[nums.length];
 7         int start = 0, end = nums.length - 1;
 8         int index = a > 0 ? nums.length - 1 : 0;
 9         while (start <= end) {
10             if (a > 0) {
11                 result[index--] = getF(nums[start], a, b, c) > getF(nums[end], a, b, c) ? getF(nums[start++], a, b, c) : getF(nums[end--], a, b, c);
12             } else {
13                 result[index++] = getF(nums[start], a, b, c) < getF(nums[end], a, b, c) ? getF(nums[start++], a, b, c) : getF(nums[end--], a, b, c);
14             }
15         }
16         return result;
17     }
18     
19     private int getF(int x, int a, int b, int c) {
20         return a * x * x + b * x + c;
21     }
22 }

 

1. This is a parabola function. So two ends always larger than mid.

2. remember return value.