[Leetcode] Is Subsequence
阿新 • • 發佈:2018-12-24
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"
"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?
public class Solution { public boolean isSubsequence(String s, String t) { int len1=s.length(); int len2=t.length(); int index1=0; int index2=0; while(index1<len1&&index2<len2) { if(t.charAt(index2)==s.charAt(index1)) index1++; index2++; } if(index1==len1) return true; else return false; } }