LeetCode:House Robber

problem:

You are a professional robber planning to rob houses along a street. Each house has a certain amount of money stashed, the only constraint stopping you from robbing each of them is that adjacent houses have security system connected and it will automatically contact the police if two adjacent houses were broken into on the same night.

Given a list of non-negative integers representing the amount of money of each house, determine the maximum amount of money you can rob tonight without alerting the police.

题目的意思就是，有一个强盗在一条街上投财富，但是不能连续偷两家的财富，否则会除非报警系统，现在让你设计一个算法求出它最大可获得的财富，很明显，这道题目需要使用DP来解决

 
int rob(vector<int>& nums) {        int len=nums.size();       if(len==0)       return 0;       if(len==1)       return nums[0];       if(len==2)       return max(nums[0],nums[1]);       vector<int> f(len,0);//用来保存中间状态，即每次可以获得的最大财富       f[0]=nums[0];       f[1]=max(nums[0],nums[1]);       for(int i=2;i<len;i++)       {           f[i]=max(f[i-2]+nums[i],f[i-1]);       }       return f[len-1];    }