Contiguous Array

1public int findMaxLength(int[] nums) {
2    Map<Integer, Integer> map = new HashMap<>();
3    map.put(0, -1);
4    int sum = 0;
5    int maxLength = 0;
6
7    for (int i = 0; i < nums.length; i++) {
8        sum += (nums[i] == 0 ? -1 : 1);
9        if (map.containsKey(sum)) {
10            maxLength = Math.max(maxLength, i - map.get(sum));
11        } else {
12            map.put(sum, i);
13        }
14    }
15
16    return maxLength;
17}