# Program to find length of longest distinct sublist in Python

Suppose we have a list of numbers called nums, and we have to find the length of the longest contiguous sublist where all its elements are unique.

So, if the input is like nums = [6, 2, 4, 6, 3, 4, 5, 2], then the output will be 5, as the longest list of unique elements is [6, 3, 4, 5, 2].

To solve this, we will follow these steps −

• head := 0, dct := a new map

• max_dist := 0

• for each index i and element num in nums, do

• if num is in dct and dct[num] >= head, then

• head := dct[num] + 1

• dct[num] := i

• if i - head + 1 > max_dist, then

• max_dist := i - head + 1

• return max_dist

Let us see the following implementation to get better understanding −

## Example

Live Demo

class Solution:
def solve(self, nums):
dct = {}
max_dist = 0
for i, num in enumerate(nums):
if num in dct and dct[num] >= head:
dct[num] = i
if i - head + 1 > max_dist:
max_dist = i - head + 1
return max_dist
ob = Solution()
nums = [6, 2, 4, 6, 3, 4, 5, 2]
print(ob.solve(nums))

## Input

[6, 2, 4, 6, 3, 4, 5, 2]

## Output

5