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# 0562. Longest Line of Consecutive One in Matrix

<https://leetcode.com/problems/longest-line-of-consecutive-one-in-matrix>

## Description

Given an `m x n` binary matrix `mat`, return *the length of the longest line of consecutive one in the matrix*.

The line could be horizontal, vertical, diagonal, or anti-diagonal.

**Example 1:**

![](https://assets.leetcode.com/uploads/2021/04/24/long1-grid.jpg)

```
**Input:** mat = [[0,1,1,0],[0,1,1,0],[0,0,0,1]]
**Output:** 3
```

**Example 2:**

![](https://assets.leetcode.com/uploads/2021/04/24/long2-grid.jpg)

```
**Input:** mat = [[1,1,1,1],[0,1,1,0],[0,0,0,1]]
**Output:** 4
```

**Constraints:**

* `m == mat.length`
* `n == mat[i].length`
* `1 <= m, n <= 104`
* `1 <= m * n <= 104`
* `mat[i][j]` is either `0` or `1`.

## ac

```java
```