README_EN.md

198. House Robber

中文文档

Description

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 systems connected and it will automatically contact the police if two adjacent houses were broken into on the same night.

Given an integer array nums representing the amount of money of each house, return the maximum amount of money you can rob tonight without alerting the police.

 

Example 1:

Input: nums = [1,2,3,1]
Output: 4
Explanation: Rob house 1 (money = 1) and then rob house 3 (money = 3).
Total amount you can rob = 1 + 3 = 4.

Example 2:

Input: nums = [2,7,9,3,1]
Output: 12
Explanation: Rob house 1 (money = 2), rob house 3 (money = 9) and rob house 5 (money = 1).
Total amount you can rob = 2 + 9 + 1 = 12.

 

Constraints:

• 1 <= nums.length <= 100
• 0 <= nums[i] <= 400

Solutions

Python3

class Solution:
    def rob(self, nums: List[int]) -> int:
        n = len(nums)
        f = [0] * (n + 1)
        f[1] = nums[0]
        for i in range(2, n + 1):
            f[i] = max(f[i - 1], f[i - 2] + nums[i - 1])
        return f[n]

class Solution:
    def rob(self, nums: List[int]) -> int:
        f = g = 0
        for x in nums:
            f, g = max(f, g), f + x
        return max(f, g)

Java

class Solution {
    public int rob(int[] nums) {
        int n = nums.length;
        int[] f = new int[n + 1];
        f[1] = nums[0];
        for (int i = 2; i <= n; ++i) {
            f[i] = Math.max(f[i - 1], f[i - 2] + nums[i - 1]);
        }
        return f[n];
    }
}

class Solution {
    public int rob(int[] nums) {
        int f = 0, g = 0;
        for (int x : nums) {
            int ff = Math.max(f, g);
            g = f + x;
            f = ff;
        }
        return Math.max(f, g);
    }
}

C++

class Solution {
public:
    int rob(vector<int>& nums) {
        int n = nums.size();
        int f[n + 1];
        memset(f, 0, sizeof(f));
        f[1] = nums[0];
        for (int i = 2; i <= n; ++i) {
            f[i] = max(f[i - 1], f[i - 2] + nums[i - 1]);
        }
        return f[n];
    }
};

class Solution {
public:
    int rob(vector<int>& nums) {
        int f = 0, g = 0;
        for (int& x : nums) {
            int ff = max(f, g);
            g = f + x;
            f = ff;
        }
        return max(f, g);
    }
};

Go

func rob(nums []int) int {
	n := len(nums)
	f := make([]int, n+1)
	f[1] = nums[0]
	for i := 2; i <= n; i++ {
		f[i] = max(f[i-1], f[i-2]+nums[i-1])
	}
	return f[n]
}

func max(a, b int) int {
	if a > b {
		return a
	}
	return b
}

func rob(nums []int) int {
	f, g := 0, 0
	for _, x := range nums {
		f, g = max(f, g), f+x
	}
	return max(f, g)
}

func max(a, b int) int {
	if a > b {
		return a
	}
	return b
}

TypeScript

function rob(nums: number[]): number {
    const n = nums.length;
    const f: number[] = Array(n + 1).fill(0);
    f[1] = nums[0];
    for (let i = 2; i <= n; ++i) {
        f[i] = Math.max(f[i - 1], f[i - 2] + nums[i - 1]);
    }
    return f[n];
}

function rob(nums: number[]): number {
    let [f, g] = [0, 0];
    for (const x of nums) {
        [f, g] = [Math.max(f, g), f + x];
    }
    return Math.max(f, g);
}

Rust

impl Solution {
    pub fn rob(nums: Vec<i32>) -> i32 {
        let mut f = [0, 0];
        for x in nums {
            f = [f[0].max(f[1]), f[0] + x]
        }
        f[0].max(f[1])
    }
}

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