LeetCode 55 Jump Game

题目

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.

Determine if you are able to reach the last index.

Example:

A = [2,3,1,1,4], return true.

A = [3,2,1,0,4], return false.

解法

用right表示走第i步之前能够跳跃到的最大距离，如果这个距离小于i内则表示不可达，否则表示可达，更新right的值。如果最后right大于或等于数组长度，则为true。

class Solution {
public:
bool canJump(vector<int>& nums) {
int right = 0;
for(int i = 0; i < nums.size(); i++) {
if (right < i) break;
if(i+nums[i] > right) right = i+nums[i];
}
return right>=nums.size()-1;
}
};