leetcode—jump game

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.

Determine if you are able to reach the last index.

For example:

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

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

2.解法分析

如果数组中没有零，一定能到达最后一个元素，反之，如果有零，那么如果0前面的元素没有一个能直接跳到0后面的元素的话，肯定是不能到达最后的元素的。

class Solution {

public:

    bool canJump(int A[], int n) {

        // Start typing your C/C++ solution below

        // DO NOT write int main() function

        //如果数组中没有0，肯定能到达

        int max=0;

        for(int i=0;i<n-1;++i)

        {

            if(A[i]==0)

            {

                if(i>=max)return false;

                else continue;

            }

            if((i+A[i])>max)

            {

                max=i+A[i];

                if(max>=n-1)return true;

            }

        }

        return true;

    }

};