Contiguous_Array.py

"""
Given a binary array, find the maximum length of a contiguous subarray with equal number of 0 and 1.

Example 1:
Input: [0,1]
Output: 2
Explanation: [0, 1] is the longest contiguous subarray with equal number of 0 and 1.

Example 2:
Input: [0,1,0]
Output: 2
Explanation: [0, 1] (or [1, 0]) is a longest contiguous subarray with equal number of 0 and 1.

Note: The length of the given binary array will not exceed 50,000. 
"""

class Solution:
    def findMaxLength(self, nums: List[int]) -> int:
        count = 0
        maxlen = 0
        d = {0:-1}
        for i in range(len(nums)):
            count = (count + 1) if (nums[i]==1) else (count -1)
            if count == 0:
                maxlen = max(maxlen, i-d[count])
            else:
                d[count] = i
            print(d, maxlen)
        return maxlen