# 0773. Sliding Puzzle

https://leetcode.com/problems/sliding-puzzle

## Description

On an `2 x 3` board, there are five tiles labeled from `1` to `5`, and an empty square represented by `0`. A **move** consists of choosing `0` and a 4-directionally adjacent number and swapping it.

The state of the board is solved if and only if the board is `[[1,2,3],[4,5,0]]`.

Given the puzzle board `board`, return _the least number of moves required so that the state of the board is solved_. If it is impossible for the state of the board to be solved, return `-1`.

**Example 1:**

![](https://assets.leetcode.com/uploads/2021/06/29/slide1-grid.jpg)

```
**Input:** board = [[1,2,3],[4,0,5]]
**Output:** 1
**Explanation:** Swap the 0 and the 5 in one move.
```

**Example 2:**

![](https://assets.leetcode.com/uploads/2021/06/29/slide2-grid.jpg)

```
**Input:** board = [[1,2,3],[5,4,0]]
**Output:** -1
**Explanation:** No number of moves will make the board solved.
```

**Example 3:**

![](https://assets.leetcode.com/uploads/2021/06/29/slide3-grid.jpg)

```
**Input:** board = [[4,1,2],[5,0,3]]
**Output:** 5
**Explanation:** 5 is the smallest number of moves that solves the board.
An example path:
After move 0: [[4,1,2],[5,0,3]]
After move 1: [[4,1,2],[0,5,3]]
After move 2: [[0,1,2],[4,5,3]]
After move 3: [[1,0,2],[4,5,3]]
After move 4: [[1,2,0],[4,5,3]]
After move 5: [[1,2,3],[4,5,0]]
```

**Example 4:**

![](https://assets.leetcode.com/uploads/2021/06/29/slide4-grid.jpg)

```
**Input:** board = [[3,2,4],[1,5,0]]
**Output:** 14
```

**Constraints:**

* `board.length == 2`
* `board[i].length == 3`
* `0 <= board[i][j] <= 5`
* Each value `board[i][j]` is **unique**.

## ac

```java
```
