978.最长涡流子数组

T376变形，本题要求连续

class Solution {
    public int maxTurbulenceSize(int[] arr) {
        int len = arr.length;
        int up = 1, down = 1, result = 1;
        for(int i = 1; i < len; i++){
            if(arr[i] > arr[i - 1]){
                up = down + 1;
                down = 1;
            }else if(arr[i] < arr[i - 1]){
                down = up + 1;
                up = 1;
            }else{
                up = 1;
                down = 1;
            }
            result = Math.max(result, Math.max(up, down));
        }
        return result;
    }
}