Jump Game II

leetcode 贪心

https://leetcode.com/problems/jump-game-ii/

class Solution {
public:
    int jump(vector<int>& nums) {
        int n=nums.size();
        int step=0;//记录步数
        int left=0;
        int right=0;//记录左右可达范围
        if(n==1) return 0;
        while(left<=right)
        {
            step++;
            int old_right=right;
            //在左右边界中找下一个最大边界
            for(int i=left;i<=old_right;i++)
            {
                int new_right=i+nums[i];//记录当前可到达最大边界
                if(new_right>=n-1)
                {
                    //k可到达，返回步数
                    return step;
                }
                if(new_right>right)
                {
                    //更新当前可到达最大右边界值
                    right=new_right;
                }
            }
            //左边界更新到原来的右边界右边
            left=old_right+1;
        }
    }
};