LeetCode - Strings - Is Subsequence 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. class Solution { public boolean isSubsequence(String s, String t) { char[] s_array = s.toCharArray(); int previndex = -1; int j=0; for(int i=0;i<t.length();i++){ if(j==s.length()) return true; if(t.charAt(i) == s.charAt(j)) j++; } return j==s.length(); } }