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).
Input: s = "abc", t = "ahbgdc" Output: true
Input: s = "axc", t = "ahbgdc" Output: false
- 0 <= s.length <= 100
- 0 <= t.length <= 10^4
- s and t consist only of lowercase English letters.
I solved this problem like this.
- Time complexity : O(N)
- Space complexity : O(1)
- if s len is 0, return True
- confirm s text(using s_idx) in t while for statement.
class Solution: def isSubsequence(self, s: str, t: str) -> bool: if not len(s): return True s_idx = 0 for _t in t: if s[s_idx] == _t: s_idx += 1 if s_idx >= len(s): return True return False