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Is Subsequence

Problem Statement​

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).

Leetcode Link

Example 1:​

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

Example 2:​

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

Constraints:​

  • 0 <= s.length <= 100
  • 0 <= t.length <= 104
  • s and t consist only of lowercase English letters.

Code​

Python Code

class Solution:
    def isSubsequence(self, s: str, t: str) -> bool:
        if len(s) > len(t):return False
        if len(s) == 0:return True
        subsequence=0
        for i in range(0,len(t)):
            if subsequence <= len(s) -1:
                print(s[subsequence])
                if s[subsequence]==t[i]:

                    subsequence+=1
        return  subsequence == len(s)