# 1615. Maximal Network Rank

<https://leetcode.com/problems/maximal-network-rank>

## Description

There is an infrastructure of `n` cities with some number of `roads` connecting these cities. Each `roads[i] = [ai, bi]` indicates that there is a bidirectional road between cities `ai` and `bi`.

The **network rank**of **two different cities** is defined as the total number of **directly** connected roads to **either** city. If a road is directly connected to both cities, it is only counted **once**.

The **maximal network rank** of the infrastructure is the **maximum network rank** of all pairs of different cities.

Given the integer `n` and the array `roads`, return *the **maximal network rank** of the entire infrastructure*.

**Example 1:**

![](https://assets.leetcode.com/uploads/2020/09/21/ex1.png)

```
**Input:** n = 4, roads = [[0,1],[0,3],[1,2],[1,3]]
**Output:** 4
**Explanation:** The network rank of cities 0 and 1 is 4 as there are 4 roads that are connected to either 0 or 1. The road between 0 and 1 is only counted once.
```

**Example 2:**

![](https://assets.leetcode.com/uploads/2020/09/21/ex2.png)

```
**Input:** n = 5, roads = [[0,1],[0,3],[1,2],[1,3],[2,3],[2,4]]
**Output:** 5
**Explanation:** There are 5 roads that are connected to cities 1 or 2.
```

**Example 3:**

```
**Input:** n = 8, roads = [[0,1],[1,2],[2,3],[2,4],[5,6],[5,7]]
**Output:** 5
**Explanation:** The network rank of 2 and 5 is 5. Notice that all the cities do not have to be connected.
```

**Constraints:**

* `2 <= n <= 100`
* `0 <= roads.length <= n * (n - 1) / 2`
* `roads[i].length == 2`
* `0 <= ai, bi <= n-1`
* `ai != bi`
* Each pair of cities has **at most one** road connecting them.

## ac

```java
```