main6.cpp

/// Source : https://leetcode.com/problems/house-robber/description/
/// Author : liuyubobobo
/// Time   : 2017-11-19

#include <iostream>
#include <vector>

using namespace std;

/// Dynamic Programming with O(1) space
/// Another way to define the states
/// Time Complexity: O(n)
/// Space Complexity: O(1)
class Solution {

public:
    int rob(vector<int>& nums) {

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

        int curMax = 0, preMax = 0;
        for(int i = 0 ; i < n ; i ++){
            int temp = curMax;
            curMax = max(curMax, nums[i] + preMax);
            preMax = temp;
        }

        return curMax;
    }
};

int main() {

    int nums[] = {2, 1};
    vector<int> vec(nums, nums + sizeof(nums)/sizeof(int));

    cout << Solution().rob(vec) << endl;

    return 0;
}