蜗牛（基础动态规划）

 1 import java.util.Scanner;
 2 // 1:无需package
 3 // 2: 类名必须Main, 不可修改
 4 
 5 public class Main {
 6     public static void main(String[] args) {
 7         Scanner sc = new Scanner(System.in);
 8         int n = sc.nextInt();
 9         int[] x = new int[n+1];
10         int[] a = new int[n+1];
11         int[] b = new int[n+1];
12         for(int i = 1;i<=n;i++){
13             x[i] = sc.nextInt();
14         }
15         for(int i = 1;i<n;i++){
16             a[i] = sc.nextInt();
17             b[i+1] = sc.nextInt();
18         }
19 
20         double[][] dp = new double[n+1][2];
21         dp[1][0] = x[1];
22         dp[1][1] = x[1] + a[1]/0.7;
23 
24 
25         for(int i = 2;i <= n;i++){
26             if(a[i]>b[i]){
27                 dp[i][1] = Math.min(dp[i-1][0] + x[i]-x[i-1] + a[i]/0.7, dp[i-1][1] + (a[i]-b[i])/0.7);
28             }else {
29                 dp[i][1] = Math.min(dp[i-1][0] + x[i]-x[i-1] + a[i]/0.7,dp[i-1][1] + (b[i]-a[i]) /1.3);
30             }
31             dp[i][0] = Math.min(dp[i-1][1] +b[i]/1.3 ,dp[i-1][0]+x[i]-x[i-1]);
32 
33         }
34 
35 
36         System.out.printf("%.2f",dp[n][0]);
37         //在此输入您的代码...
38         sc.close();
39     }
40 }