House Robber

代码如下，注释部分为递归版本，在OJ上运行超时，在本地正常，所以选择迭代版本。
代码如下：

#include<iostream>
#include<vector>
using namespace std;

class Solution {
public:
    int rob(vector<int>& nums) {
        int hasFinal, exceptFinal;

        if(nums.size() == 0)
            return 0;

        if(nums.size() == 1)
            return nums[0];

        if(nums.size() == 2) {
            if(nums[0] > nums[1])
                return nums[0];
            else
                return nums[1];
        }

        int tmp1, tmp2;
        int maxNM1 = max(nums[0], nums[1]);
        int maxNM2 = nums[0];
        int maxN;
        for(int i = 3; i <= nums.size(); i++) {
            if(i != 3) {
                maxNM2 = maxNM1;
                maxNM1 = maxN;
            }

            tmp1 = maxNM2 + nums[i - 1];
            tmp2 = maxNM1;
            maxN = max(tmp1, tmp2);
        }

        return maxN;


        //recursive version
        /*int hasFinal, exceptFinal;

        if(nums.size() == 0)
            return 0;

        if(nums.size() == 1)
            return nums[0];

        if(nums.size() == 2) {
            if(nums[0] > nums[1])
                return nums[0];
            else
                return nums[1];
        }

        if(nums.size() == 3) {
            hasFinal = nums[0] + nums[2];
            if(nums[0] > nums[1])
                exceptFinal = nums[0];
            else
                exceptFinal = nums[1];
            if(hasFinal > exceptFinal)
                return hasFinal;
            else
                return exceptFinal;
        }


        //int hasFinal, exceptFinal;
        vector<int> arr1(nums.begin(), nums.end() - 2);
        vector<int> arr2(nums.begin(), nums.end() - 1);
        hasFinal = rob(arr1) + *(nums.end() - 1);
        exceptFinal = rob(arr2);
        if(hasFinal > exceptFinal)
            return hasFinal;
        else
            return exceptFinal;*/
    }
};

int main() {
    vector<int> arr;
    arr.push_back(5);arr.push_back(4);arr.push_back(1);arr.push_back(6);
    arr.push_back(57);arr.push_back(24);arr.push_back(48);arr.push_back(12);
    Solution solution;
    cout << solution.rob(arr) << endl;
    getchar();
}