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# 0392. Is Subsequence

<https://leetcode.com/problems/is-subsequence>

## 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:**

```
**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.

**Follow up:** Suppose there are lots of incoming `s`, say `s1, s2, ..., sk` where `k >= 109`, and you want to check one by one to see if `t` has its subsequence. In this scenario, how would you change your code?

## ac

```java
```