题解 | 最小花费爬楼梯

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

int main() {
    int n;
    cin >> n;
    vector<int> cost(n);
    for(int i = 0; i < n; i++) {
        cin >> cost[i];
    }
    
    vector<int> dp(n);
    dp[0] = cost[0];
    dp[1] = cost[1];
    
    for(int i = 2; i < n; i++) {
        dp[i] = min(dp[i-1], dp[i-2]) + cost[i];
    }
    
    cout << min(dp[n-1], dp[n-2]) << endl;
    return 0;
}

import java.util.Scanner;

public class Main {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        int n = sc.nextInt();
        int[] cost = new int[n];
        for(int i = 0; i < n; i++) {
            cost[i] = sc.nextInt();
        }
        
        int[] dp = new int[n];
        dp[0] = cost[0];
        dp[1] = cost[1];
        
        for(int i = 2; i < n; i++) {
            dp[i] = Math.min(dp[i-1], dp[i-2]) + cost[i];
        }
        
        System.out.println(Math.min(dp[n-1], dp[n-2]));
        sc.close();
    }
}

n = int(input())
cost = list(map(int, input().split()))

dp = [0] * n
dp[0] = cost[0]
dp[1] = cost[1]

for i in range(2, n):
    dp[i] = min(dp[i-1], dp[i-2]) + cost[i]

print(min(dp[n-1], dp[n-2]))