Interview Course Based on Story Questions

# Problem statement

Given an unsorted array of integers, find the length of the longest consecutive elements sequence.


## Input

The input will be an array of integers. The following is an example input:



```
[9,1,4,7,3,-1,0,5,8,-1,6]
```

## Output

The output will be a single integer representing the length of the largest consecutive sequence in the input array. The following is an example output of the above input:


```
Output: 7
```

There are `7` consecutive integers in the input array,  `[3, 4, 5, 6, 7, 8, 9]`.

# Coding exercise

You need to implement the  `LCS(arr)` function, where `arr` is the array of unsorted integers. The function will return a single integer; this will be the length of the largest consecutive sequence present in `arr`.
