> For the complete documentation index, see [llms.txt](https://jaywin.gitbook.io/leetcode/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://jaywin.gitbook.io/leetcode/solutions/1263-minimum-moves-to-move-a-box-to-their-target-location.md).

# 1263. Minimum Moves to Move a Box to Their Target Location

<https://leetcode.com/problems/minimum-moves-to-move-a-box-to-their-target-location>

## Description

A storekeeper is a game in which the player pushes boxes around in a warehouse trying to get them to target locations.

The game is represented by an `m x n` grid of characters `grid` where each element is a wall, floor, or box.

Your task is to move the box `'B'` to the target position `'T'` under the following rules:

* The character `'S'` represents the player. The player can move up, down, left, right in `grid` if it is a floor (empty cell).
* The character `'.'` represents the floor which means a free cell to walk.
* The character `'#'` represents the wall which means an obstacle (impossible to walk there).
* There is only one box `'B'` and one target cell `'T'` in the `grid`.
* The box can be moved to an adjacent free cell by standing next to the box and then moving in the direction of the box. This is a **push**.
* The player cannot walk through the box.

Return *the minimum number of **pushes** to move the box to the target*. If there is no way to reach the target, return `-1`.

**Example 1:**

![](https://assets.leetcode.com/uploads/2019/11/06/sample_1_1620.png)

```
**Input:** grid = [["#","#","#","#","#","#"],
               ["#","T","#","#","#","#"],
               ["#",".",".","B",".","#"],
               ["#",".","#","#",".","#"],
               ["#",".",".",".","S","#"],
               ["#","#","#","#","#","#"]]
**Output:** 3
**Explanation:** We return only the number of times the box is pushed.
```

**Example 2:**

```
**Input:** grid = [["#","#","#","#","#","#"],
               ["#","T","#","#","#","#"],
               ["#",".",".","B",".","#"],
               ["#","#","#","#",".","#"],
               ["#",".",".",".","S","#"],
               ["#","#","#","#","#","#"]]
**Output:** -1
```

**Example 3:**

```
**Input:** grid = [["#","#","#","#","#","#"],
               ["#","T",".",".","#","#"],
               ["#",".","#","B",".","#"],
               ["#",".",".",".",".","#"],
               ["#",".",".",".","S","#"],
               ["#","#","#","#","#","#"]]
**Output:** 5
**Explanation:**  push the box down, left, left, up and up.
```

**Example 4:**

```
**Input:** grid = [["#","#","#","#","#","#","#"],
               ["#","S","#",".","B","T","#"],
               ["#","#","#","#","#","#","#"]]
**Output:** -1
```

**Constraints:**

* `m == grid.length`
* `n == grid[i].length`
* `1 <= m, n <= 20`
* `grid` contains only characters `'.'`, `'#'`, `'S'`, `'T'`, or `'B'`.
* There is only one character `'S'`, `'B'`, and `'T'` in the `grid`.

## ac

```java
```