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Leetcode
Easy
Two Pointers
Strings
Is Subsequence
Check whether one string is a subsequence of another.
Acceptance 0%
Problem Statement
Problem
Given two strings s and t, determine whether s is a subsequence of t.
A string s is a subsequence of t if all characters of s appear in t in the same relative order, but not necessarily contiguously.
Return true if s is a subsequence of t; otherwise return false.
Notes
- You may skip characters in
t. - The characters of
smust appear in order. - An empty string is a subsequence of any string.
Input Format
- Two strings
sandt. sis the candidate subsequence.tis the reference string to scan.
Output Format
- Return a boolean value.
trueifsis a subsequence oft, otherwisefalse.
Constraints
- Strings contain lowercase English letters in the standard formulation of this problem.
- Time complexity should be linear in the length of
t.
Examples
Sample cases returned by the problem API.
Example 1
Input
s = "abc" t = "ahbgdc"
Output
true
Explanation
You can match 'a', then 'b', then 'c' in order while skipping other characters in t.
Example 2
Input
s = "axc" t = "ahbgdc"
Output
false
Explanation
There is no 'x' in t, so s cannot be formed as a subsequence.
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