题解 | #不能连续吃草的牛II#

import java.util.*;


public class Solution {
    /**
     依然是利用动态规划的滑动窗口方法，降低了空间复杂度。
     */
    public int eatGrass (int[] nums) {
        // write code here
        if (nums.length == 1) {
            return nums[0];
        }
        if (nums.length == 2) {
            return Math.max(nums[0], nums[1]);
        }
        int x1=nums[0],y1=Math.max(nums[0],nums[1]),z1=0;
        int x2=0,y2=nums[1],z2=0;
        for (int i = 2; i < nums.length - 1; i++) {
            z1 = Math.max(y1, x1 + nums[i]);
            x1=y1;
            y1=z1;
            z2 = Math.max(y2, x2 + nums[i]);
            x2=y2;
            y2=z2;
        }
        z2 = Math.max(y2, x2+ nums[nums.length-1]);
        return Math.max(z2, z1);
    }
}