中南大学计算机研究生复试——上机考试

import java.util.ArrayList; import java.util.Collections; import java.util.List; import java.util.Scanner; public class Discount { public static void main(String[] args) { Scanner sc = new Scanner(System.in); int num = sc.nextInt(); int moneyCount = sc.nextInt(); List<Person> list = new ArrayList<Person>(); for (int i = 0; i < num; i++) { Person p = new Person(); p.setDiscount(sc.nextDouble()); p.setMoney(sc.nextInt()); list.add(p); } // 计算最大上限 int maxMoney = 0; for (Person p1 : list) { maxMoney += p1.getMoney(); } // 对折扣进行排序 Collections.sort(list); // 如果总价小于所有折扣率上线之和 // 则用一循环从折扣率最低一直到折扣到总数 int minMoney = 0; if (maxMoney > moneyCount) { // 存放前n项和 int current3 = 0; int current = 0, i, current2 = 0; for (i = 0; i < list.size(); i++) { current += list.get(i).getMoney(); if (current > moneyCount) { break; } } for (int j = 0; j < i; j++) { current2 += list.get(j).getMoney() * list.get(j).getDiscount(); } for (int x = 0; x < i; x++) { current3 += list.get(x).getMoney(); } minMoney = (int) (current2 + (moneyCount - current3) * list.get(i).getDiscount()); System.out.println(minMoney); } // 如果总价大于所有折扣率上线之和那么就是所有人都折扣完，剩余的钱按照原价付 if (maxMoney <= moneyCount) { int currentMoney1 = 0, currentMoney2 = 0; for (int i = 0; i < list.size(); i++) { currentMoney2 += list.get(i).getMoney(); currentMoney1 += (int) (list.get(i).getMoney() * list.get(i) .getDiscount()); } minMoney = currentMoney1 + (moneyCount - currentMoney2); System.out.println(minMoney); } } } class Person implements Comparable<Person> { private double discount; private int money; public double getDiscount() { return discount; } public void setDiscount(double discount) { this.discount = discount; } public int getMoney() { return money; } public void setMoney(int money) { this.money = money; } // 用于比较 public int compareTo(Person p) { if (discount != p.getDiscount()) { // 升序排列 if (discount < p.getDiscount()) { return -1; } if (discount > p.getDiscount()) { return 1; } return 0; } else { // 降序排列 return p.getMoney() - money; } } // 判断两个对象是否相等 public boolean equals(Object obj) { if (obj instanceof Person) { Person p = (Person) obj; if ((discount == p.getDiscount()) && (money == p.getMoney())) { return true; } else { return true; } } else { return false; } } }