leetcode------Jump Game II

标题: Jump Game II
通过率: 24.5
难度:

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.)

贪心算法

每次遍历一遍可以到达的最远距离之内的所有节点,找出可以到达的最远节点,然后继续找,

每走一个最远就加一步

 1 public class Solution {
 2     public int jump(int[] A) {
 3         int step=0,lastMax=0,max=0;
 4         for(int i=0;i<A.length;){
 5             if(lastMax>=A.length-1)break;
 6             while(i<=lastMax){
 7                 if(i+A[i]>max){
 8                     max=i+A[i];
 9                 }
10                 i++;
11             }
12             if(lastMax<max){
13                 lastMax=max;
14             }
15             step++;
16         }
17         return step;
18     }
19 }

 

posted @ 2015-03-29 16:31  pku_smile  阅读(166)  评论(0编辑  收藏  举报