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# 1784. Check if Binary String Has at Most One Segment of Ones

<https://leetcode.com/problems/check-if-binary-string-has-at-most-one-segment-of-ones>

## Description

Given a binary string `s` **​​​​​without leading zeros**, return `true`​​​ *if* `s` *contains **at most one contiguous segment of ones***. Otherwise, return `false`.

**Example 1:**

```
**Input:** s = "1001"
**Output:** false
**Explanation:** The ones do not form a contiguous segment.
```

**Example 2:**

```
**Input:** s = "110"
**Output:** true
```

**Constraints:**

* `1 <= s.length <= 100`
* `s[i]`​​​​ is either `'0'` or `'1'`.
* `s[0]` is `'1'`.

## ac

```java
```