day 05 Coin

coin

package com.wengkai.coins;

import com.wengkai.hash.Hash;

import java.util.HashMap;
import java.util.Scanner;

public class Coin
{
    
       //Hash表
    //所有类型必须是对象，而不能是基本元素
    private HashMap<Integer, String> coinnames = new HashMap<Integer, String>();

    public Coin()
    {
    
    
        coinnames.put(1, "penny");//key value
        coinnames.put(10, "dime");
        coinnames.put(25, "quarter");
        coinnames.put(50, "half-dolar");
        coinnames.put(50, "五毛");//唯一
        System.out.println(coinnames.keySet().size());//4
        System.out.println(coinnames);//{1=penny, 50=五毛, 25=quarter, 10=dime}
        for (Integer k : coinnames.keySet())
        {
    
    
            String s = coinnames.get(k);
            System.out.println(s);//penny 五毛 quarter dime

        }
    }

    public String getName(int amount)
    {
    
    
        if (coinnames.containsKey(amount)) return coinnames.get(amount);
        else return "NOT FOUND";
    }

    public static void main(String[] args)
    {
    
    
        Scanner in = new Scanner(System.in);
        int amount = in.nextInt();
        Coin coin = new Coin();
        String name = coin.getName(amount);
        System.out.println(name);//五毛
    }
}