如何通过用户输入结束循环

package cst150zzhw4_worst;

import java.util.Scanner;

public class CST150zzHW4_worst {

    public static void main(String[] args) {
    //Initialize Variables
    double length; // length of room
    double width; // Width of room
    double price_per_sqyd; // Total carpet needed price
    double price_for_padding; // Price for padding
    double price_for_installation; // Price for installation
        String input; // User's input to stop or reset program
    double final_price; // The actual final price
        boolean repeat = true;

    // Create a Scanner object for keyboard input.
    Scanner keyboard = new Scanner(System.in);

        while (repeat)
        {   
        //User Input

    System.out.println("\n" +"What is the length of the room?: ");
    length = keyboard.nextInt();

    System.out.println("What is the width of the room?: ");
    width = keyboard.nextInt();

    System.out.println("What is the price of the carpet per square yard?: ");
    price_per_sqyd = keyboard.nextDouble();

        System.out.println("What is the price for the padding?: ");
        price_for_padding = keyboard.nextDouble();

        System.out.println("What is the price of the installation?: ");
        price_for_installation = keyboard.nextDouble();

        final_price = (price_for_padding + price_for_installation + price_per_sqyd)*((width*length)/9);

        keyboard.nextLine(); //Skip the newline

        System.out.println("The possible total price to install the carpet will be $" + final_price + "\n" + "Type 'yes' or 'no' if this is correct: ");
        input = keyboard.nextLine();

        } 
    }
}

怎么会当用户说是程序停止并且如果用户说不时，我就这样做，那么程序只是重复一次？我不知道为什么我有这么多麻烦。我搜索了4个多小时。我想，我只应该使用while循环。

How would I make it so when the user says yes the program stop and if the user says no then the program just repeats? I don't know why I'm having so much trouble. I've searched for well over 4 hours. I am only supposed to use a while loop, I think.