Suppose we have an unsorted array of numbers, we have to find the length of the longest sequence of consecutive elements.
So, if the input is like nums = [70, 7, 50, 4, 6, 5], then the output will be 4, as the longest sequence of consecutive elements is [4, 5, 6, 7]. so we return its length: 4.
To solve this, we will follow these steps −
nums := all unique elements of nums
max_cnt := 0
for each num in nums, do
if num - 1 not in nums, then
cnt := 0
while num is present in nums, do
num := num + 1
cnt := cnt + 1
max_cnt := maximum of max_cnt and cnt
return max_cnt
Let us see the following implementation to get better understanding −
Example
class Solution: def solve(self, nums): nums = set(nums) max_cnt = 0 for num in nums: if num - 1 not in nums: cnt = 0 while num in nums: num += 1 cnt += 1 max_cnt = max(max_cnt, cnt) return max_cnt ob = Solution() nums = [70, 7, 50, 4, 6, 5] print(ob.solve(nums))
Input
[70, 7, 50, 4, 6, 5]
Output
4