Description

Given two strings s and t, return true if s is a subsequence of t, or false otherwise.
A subsequence of a string is a new string that is formed from the original string by deleting some (can be none) of the characters without disturbing the relative positions of the remaining characters. (i.e., “ace” is a subsequence of “abcde” while “aec” is not).

Example 1:

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Input: s = "abc", t = "ahbgdc"
Output: true

Example 2:

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Input: s = "axc", t = "ahbgdc"
Output: false

Constraints:

1 <= s.length <= 100
1 <= t.length <= 10^4
s and t consist only of lowercase English letters.

Approach

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class Solution:
    def isSubsequence(self, s: str, t: str) -> bool:
        i=j=0
        while i<len(s) and j<len(t):
            if s[i]==t[j]:
                i+=1
            j+=1
        return i==len(s)