LeetCode: 228. Summary Ranges
阿新 • • 發佈:2018-12-16
題目描述
Given a sorted integer array without duplicates, return the summary of its ranges.
Example 1:
Input: [0,1,2,4,5,7]
Output: ["0->2","4->5","7"]
Explanation: 0,1,2 form a continuous range; 4,5 form a continuous range.
Example 2:
Input: [0,2,3,4,6,8,9] Output: ["0","2->4","6","8->9"] Explanation: 2,3,4 form a continuous range; 8,9 form a continuous range.
解題思路
統計連續的數字,根據題意將相鄰的連續數字拼接。
AC 程式碼
class Solution { public: vector<string> summaryRanges(vector<int>& nums) { vector<string> ranges; int startIdx = 0; int cnt = 0; if(nums.empty()) return ranges; while(startIdx+cnt <= nums.size()) { if(startIdx+cnt == nums.size() || nums[startIdx]+cnt != nums[startIdx+cnt]) { if(startIdx+cnt == nums.size() && cnt == 0) { break; } ranges.push_back(to_string(nums[startIdx])); if(cnt > 1) { ranges.back() += ("->"+to_string(nums[startIdx+cnt-1])); } startIdx = startIdx+cnt; cnt = 0; } else { ++cnt; } } return ranges; } };