leetcode/167.two-sum-ii-input-array-is-sorted.js at master · tmf-map/leetcode · GitHub

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
/*
 * @lc app=leetcode id=167 lang=javascript
 *
 * [167] Two Sum II - Input array is sorted
 *
 * https://leetcode.com/problems/two-sum-ii-input-array-is-sorted/description/
 *
 * algorithms
 * Easy (50.77%)
 * Likes:    959
 * Dislikes: 402
 * Total Accepted:    266K
 * Total Submissions: 523.4K
 * Testcase Example:  '[2,7,11,15]\n9'
 *
 * Given an array of integers that is already sorted in ascending order, find
 * two numbers such that they add up to a specific target number.
 *
 * The function twoSum should return indices of the two numbers such that they
 * add up to the target, where index1 must be less than index2.
 *
 * Note:
 *
 *
 * Your returned answers (both index1 and index2) are not zero-based.
 * You may assume that each input would have exactly one solution and you may
 * not use the same element twice.
 *
 *
 * Example:
 *
 *
 * Input: numbers = [2,7,11,15], target = 9
 * Output: [1,2]
 * Explanation: The sum of 2 and 7 is 9. Therefore index1 = 1, index2 = 2.
 *
 */
/**
 * @param {number[]} numbers
 * @param {number} target
 * @return {number[]}
 */
var twoSum = function(numbers, target) {
    let lo = 0;
    let hi = numbers.length - 1;
    while (lo < hi) {
      if (numbers[lo] + numbers[hi] > target) {
        hi--;
      }
      if (numbers[lo] + numbers[hi] < target) {
        lo++;
      }
      if (numbers[lo] + numbers[hi] === target) {
        return [lo + 1, hi + 1];
      }
    }
};