LeetCode oj 392. Is Subsequence (字符串)

392. Is Subsequence

 

QuestionEditorial Solution

 My Submissions

• Total Accepted: 11558
• Total Submissions: 26312
• Difficulty: Medium
• Contributors: Admin

Given a string s and a string t, check if s is subsequence of t.

You may assume that there is only lower case English letters in both s and t. t is potentially a very long (length ~= 500,000) string, and s is a short string (<=100).

A subsequence of a string is a new string which is formed from the original string by deleting some (can be none) of the characters without disturbing the relative positions of the remaining characters. (ie, "ace" is a subsequence of "abcde" while "aec" is not).

Example 1:
s = "abc", t = "ahbgdc"

Return true.

Example 2:
s = "axc", t = "ahbgdc"

Return false.

Follow up:
If there are lots of incoming S, say S1, S2, ... , Sk where k >= 1B, and you want to check one by one to see if T has its subsequence. In this scenario, how would you change your code?

给你字符串s和t，问字符串s在不在t的子序列中

第一眼看错了，结果敲个kmp上去= =，后来发现并不要求字符连续，那就从头到尾跑一边t就行了 = =，水的不行

public class Solution {    public boolean isSubsequence(String s, String t) {        int index = 0;        int len_s = s.length();        int len_t = t.length();        if(len_s == 0)           return true;        for(int i=0;i<len_t;i++){            if(t.charAt(i) == s.charAt(index)){                index++;                if(index == len_s)                    return true;            }        }        return false;    }}