【Leetcode】Summary Ranges

题目链接：https://leetcode.com/problems/summary-ranges/

题目：

Given a sorted integer array without duplicates, return the summary of its ranges.

For example, given [0,1,2,4,5,7], return ["0->2","4->5","7"].

思路：

直接做就好了，时间复杂度O(n)

算法：

public List<String> summaryRanges(int[] nums) {List<String> result = new ArrayList<String>();if (nums.length == 1) {result.add(nums[0] + "");return result;}// 长度大于1时，因为要判断连续，至少要为2for (int i = 0; i < nums.length; i++) {int start = nums[i], j = i, end = i;for (int tmp = start; j < nums.length && nums[j] == tmp; j++, tmp++);if (j == nums.length) { // 当j到了数组最后元素end = nums[j - 1];} else {// 当不连续end = nums[--j];}i = j;if ((end == start)) {result.add(start + "");} else {result.add(start + "->" + end);}}return result;}