[LeetCode]Longest Uncommon Subsequence II

最长的非公共子序列

Posted by JinFei on August 31, 2021

题目描述

Given an array of strings strs, return the length of the longest uncommon subsequence between them. If the longest uncommon subsequence does not exist, return -1.

An uncommon subsequence between an array of strings is a string that is a subsequence of one string but not the others.

A subsequence of a string s is a string that can be obtained after deleting any number of characters from s.

For example, “abc” is a subsequence of “aebdc” because you can delete the underlined characters in “aebdc” to get “abc”. Other subsequences of “aebdc” include “aebdc”, “aeb”, and “” (empty string).

Example 1:

Input: strs = [“aba”,”cdc”,”eae”] Output: 3

Example 2:

Input: strs = [“aaa”,”aaa”,”aa”] Output: -1

Constraints:

  • 1 <= strs.length <= 50
  • 1 <= strs[i].length <= 10
  • strs[i] consists of lowercase English letters.

解题思路

C++代码

class Solution {
public:
    int findLUSlength(vector<string>& strs) {
        int res = -1;
        for(int i = 0; i < strs.size(); i++){
            int j = 0;
            for(j = 0; j < strs.size(); j++){
                if(i == j){
                    continue;
                }
                if(check(strs[i], strs[j])){
                    break;
                }

            }
            if(j == strs.size()){
                res = max(res, (int)strs[i].length());
            }
            
        }
        return res;
        
    }
    bool check(string a, string b){
        int i = 0;
        for(auto& s : b){
            if(s == a[i]){
                i++;
            }
            if(i == a.size()){
                break;
            }
        }
        
        return i == a.size();
    }
};