租用游艇问题-dp

Posted 2021-11-11 nuist__NJUPT

思想:自底向上，用dp[0][n-2]存储最少租金。

方式1：键盘输入，控制台输出

import java.util.Scanner;

public class HireYacht {
    public static int dynamic(int n, int [][] dp){
        for(int i=n-2; i>0; i--){
            for(int j=0; j<n-i;j++) {
                if (dp[i][n-i-2] + dp[i - 1][j] <= dp[i - 1][n-i-1]) {
                    dp[i - 1][n-i-1] = dp[i][n-i-2] + dp[i - 1][j] ;
                }
            }
        }
        return dp[0][n-2] ;
    }
    public static void main(String[] args) {
        Scanner input = new Scanner(System.in) ;
        int n = input.nextInt() ;
        int [][] dp = new int [n][n] ;
        for(int i=0; i<n-1; i++){
            for(int j=0; j<n-i-1; j++){
                dp[i][j] = input.nextInt() ;
            }
        }
        System.out.println(dynamic(n, dp));
    }
}

方式2：文件流输入输出。

import java.io.*;

public class HireYacht1 {
    static String line ;
    static int n, temp, j=0, k=0 ;
    static int [][] dp =  new int [10000][10000] ;
    public static int dynamic(int n, int [][] dp){
        for(int i=n-2; i>0; i--){
            for(int j=0; j<n-i;j++) {
                if (dp[i][n-i-2] + dp[i - 1][j] <= dp[i - 1][n-i-1]) {
                    dp[i - 1][n-i-1] = dp[i][n-i-2] + dp[i - 1][j] ;
                }
            }
        }
        return dp[0][n-2] ;
    }
    public static void main(String[] args) {
        try(FileInputStream fileInputStream = new FileInputStream("D:\\\\study\\\\input.txt");
            DataInputStream dataInputStream = new DataInputStream(new BufferedInputStream(fileInputStream))){
            line = dataInputStream.readLine() ;
            n = Integer.parseInt(line) ;
            temp = n ;
            while(n > 1){
                line = dataInputStream.readLine() ;
                String [] s = line.split("[ ]") ;
                for(int i=0; i<s.length; i++){
                    dp[j][k] = Integer.parseInt(s[i]) ;
                    if(k<n-i-1){
                        k ++ ;
                    }
                }
                j ++;
                k = 0 ;
                n -- ;
            }
        } catch (FileNotFoundException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        }

        try(FileOutputStream fileOutputStream = new FileOutputStream("D:\\\\study\\\\output.txt");
            DataOutputStream dataOutputStream = new DataOutputStream(new BufferedOutputStream(fileOutputStream))) {
            int result = dynamic(temp, dp) ;
            dataOutputStream.writeBytes(String.valueOf(result));
        } catch (FileNotFoundException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
}