LeetCode 392. 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 andt. t is potentially a very long (length ~= 500,000) string, ands 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:    bool isSubsequence(string s, string t) {        int i=0,j=0;        while(i<s.size() && j<t.size()){            if(s.at(i)==t.at(j)){                i++;                j++;            }else{                j++;            }        }        if(i<s.size()){            return false;        }else{            return true;        }    }};