Untitled

import java.util.HashMap;

public class ContiguousArray {
    public int findMaxLength(int[] nums) {
        // Replace 0 with -1 to handle the sum logic
        int maxLength = 0;
        int prefixSum = 0;
        HashMap<Integer, Integer> map = new HashMap<>();
        
        // Add a base case to handle the entire array summing to zero
        map.put(0, 0);
        
        for (int i = 0; i < nums.length; i++) {
            prefixSum += (nums[i] == 0) ? -1 : 1;
            
            if (map.containsKey(prefixSum)) {
                // If prefixSum exists, calculate the subarray length
                maxLength = Math.max(maxLength, i+1 - map.get(prefixSum) + 1);
            } else {
                // Otherwise, store the first occurrence of the prefixSum
                map.put(prefixSum, i+1);
            }
        }
        
        return maxLength;
    }
    
    public static void main(String[] args) {
        ContiguousArray solution = new ContiguousArray();
        System.out.println(solution.findMaxLength(new int[]{0, 1})); // Output: 2
        System.out.println(solution.findMaxLength(new int[]{0, 1, 0})); // Output: 2
    }
}