# 1436. Destination City

https://leetcode.com/problems/destination-city

## Description

You are given the array `paths`, where `paths[i] = [cityAi, cityBi]` means there exists a direct path going from `cityAi` to `cityBi`. _Return the destination city, that is, the city without any path outgoing to another city._

It is guaranteed that the graph of paths forms a line without any loop, therefore, there will be exactly one destination city.

**Example 1:**

```
**Input:** paths = [["London","New York"],["New York","Lima"],["Lima","Sao Paulo"]]
**Output:** "Sao Paulo" 
**Explanation:** Starting at "London" city you will reach "Sao Paulo" city which is the destination city. Your trip consist of: "London" -> "New York" -> "Lima" -> "Sao Paulo".
```

**Example 2:**

```
**Input:** paths = [["B","C"],["D","B"],["C","A"]]
**Output:** "A"
**Explanation:** All possible trips are: 
"D" -> "B" -> "C" -> "A". 
"B" -> "C" -> "A". 
"C" -> "A". 
"A". 
Clearly the destination city is "A".
```

**Example 3:**

```
**Input:** paths = [["A","Z"]]
**Output:** "Z"
```

**Constraints:**

* `1 <= paths.length <= 100`
* `paths[i].length == 2`
* `1 <= cityAi.length, cityBi.length <= 10`
* `cityAi != cityBi`
* All strings consist of lowercase and uppercase English letters and the space character.

## ac

```java
```
