LeetCode 17 Jump Game II

1、题目描述
Given an array of non-negative integers, you are initially positioned at the first index of the array.
Each element in the array represents your maximum jump length at that position.
Your goal is to reach the last index in the minimum number of jumps.
For example:
Given array A = [2,3,1,1,4]
The minimum number of jumps to reach the last index is 2. (Jump 1 step from index 0 to 1, then 3 steps to the last index.)
2、解题思路
这道题目是Jump Game旳延伸，我们使用正向思维，并且这里我们不在仅仅考虑每一步的全局最优，而是考虑当前步step可以到达的最大位置和上一步step-1到达的最大位置，只有在前者比后者大的条件下，我们才考虑更新step。这样即可求得最小步数。
3、实现代码

class Solution {public:    int jump(vector<int>& nums) {        auto n=nums.size();        int step=0,curmax=0;        for(int i=0; curmax<(n-1)&& i<n && i<=curmax;i++){            if ((nums[i]+i)>curmax){                step+=1;                curmax=nums[i]+i;            }        }        if (curmax<(n-1)) return 0;        return step;    }};