Question

大家好我是Java的新手，我有一个示例问题。我也有自己的解决方案。有没有其他更好的方法来解决这个问题？

在遥远的王国，有数字战。在那个王国中的国王要求你创建一个程序，以确定该事件的获胜者/冠军。参赛者人数未定。比赛的胜者通常是BIGGEST号码。这场比赛是一场淘汰赛。比赛的顺序是First IN vs Last IN，Second In vs Last Second In等等......如果某个特定号码没有对手，他或她将被视为默认赢家。

示例输出：

输入参赛人数：5

参加参赛者＃1：50

参加参赛者＃2：30

参加参赛者＃3：8

参加参赛者＃4：11

参加参赛者＃5：20

模拟：

第一轮：50比20胜者：50

第2轮：30比11胜者：30

第3轮：默认获胜者是：8

下一步......

第4轮：50比8胜者：50

第5轮：默认赢家为30

下一步......

第六轮：50比30胜者：50

冠军：50

总括号匹配：3

总回合数：6

我的解决方案：

import java.util.Scanner;

public class BattleofNumbers{
public static void main(String[] args){
    double num1, num2, num3, num4, num5;
    double chal1, chal2, chal3, champion;
    double bracket, round = 0;

    System.out.println("Please Enter 5 Numbers: ");
    System.out.println("");

    Scanner in = new Scanner(System.in);
    num1 = in.nextDouble();
    num2 = in.nextDouble();
    num3 = in.nextDouble();
    num4 = in.nextDouble();
    num5 = in.nextDouble();

    System.out.println("");

    if (num1 > num5){
        chal1 = num1;
        round++;
        System.out.println("Round 1 Winner: " + chal1);
        }
    else{
        chal1 = num5;
        round++;
        System.out.println("Round 1 Winner: " + chal1);
    }
    if (num2>num4){
        chal2 = num2;
        round++;
        System.out.println("Round 2 Winner: " + chal2);
    }else{
        chal2 = num4;
        round++;
        System.out.println("Round 2 Winner: " + chal2);
    }
    if (chal1>num3){
        chal3 = chal1;
        round++;
        System.out.println("Round 3 Winner: " + chal3);
    }else{
        chal3 = num3;
        round++;
        System.out.println("Round 3 Winner: " +chal3);
    }
    if (chal3 > chal2){
        champion = chal3;
        round++;
        System.out.println("Round 4 Winner: " + champion);
    }else{
        champion = chal2;
        round++;
        System.out.println("Round 4 Winner: " + champion);
    }
    bracket = round / 2;
    System.out.println("=====================");

    System.out.println("The Champion: " + champion);
    System.out.println("No. of Rounds: " + round );
    System.out.println("No. of Brackets: " + bracket);
    }
}

Answer 1

我不知道你是多么有经验，但你应该使用数组而不是5个单变量：double[] nums = new double[5];。此外，变量＆＃34;括号＆＃34;不需要因为它总是圆/ 2所以你可以替换它：System.out.println("No. of Brackets: " + round/2);

因为在if-和else-block中都使用了每个if-else-block的第2行和第3行，所以你应该将它们外包（从而减少代码量）：

if (num1 > num5){
 chal1 = num1;
 // round++;
 // System.out.println("Round 1 Winner: " + chal1);
 }
else {
 chal1 = num5;
 // round++;
 // System.out.println("Round 1 Winner: " + chal1);
 }
round++;
System.out.println("Round 1 Winner: " + chal1);

＆＃34;轮＆＃34;似乎是4的常数。你可以停止计算它，并用4表示它：double round = 4;

Answer 2

此解决方案向您展示如何使用ArrayList进行此类操作（以及如何在实际代码中使用它）：

import java.util.ArrayList;
import java.util.Scanner;

public class Prog{
    public static void main(String[] args){
      ArrayList<Double> nums = new ArrayList<Double>();
      Scanner in = new Scanner(System.in);
      System.out.println("How many contestants are there? ");
      int size = in.nextInt();
      while(size-- > 0){
        System.out.println("Contestant: ");
        nums.add(in.nextDouble());
      }
      while(nums.size() > 1){
        System.out.println("ROUND STARTED, contestants are: " + nums);
        int i = 0;

        while(i < nums.size()){
          nums.set(i, Math.max(nums.get(i), nums.get(nums.size()-1)));
          if(i != nums.size() - 1)
            nums.remove(nums.size() -1);
          i++;
        }
      }
      System.out.println("Competition has ended, the winner is: " + nums.get(0));
    }
}

Answer 3

我尝试了一个使用数组的小实现，我称之为半递归。我确定它并不完美，但它是一种更通用的方法，因为输入数量是动态的，条件检查只编程一次。随意提供反馈，也许有人有想法递归执行每个检查。

import java.util.Scanner;

public class BattleofNumbers {

  double[] nums;
  int amount, round = 0;

  double champ;

  Scanner in;

  public BattleofNumbers() {
      in = new Scanner(System.in);
      initValues();
      processGame();
  }

  public void processGame() {
      champ = calcChamp(nums);
      System.out.println("=====================");
      System.out.println("The Champion: " + champ);
      System.out.println("No. of Rounds: " + round);
      System.out.println("No. of Brackets: "
            + (int) Math.ceil((double) round / 2));
  }

  private void initValues() {
      System.out.println("Please enter amount of numbers:");
      amount = in.nextInt();

      nums = new double[amount];

      for (int i = 0; i < amount; i++) {
          System.out.println("Please enter " + (i + 1) + ". number:");
          nums[i] = in.nextDouble();
      }

      System.out.println("");
  }

  public double calcChamp(double[] nums) {
      double[] nexts = new double[(int)Math.ceil(((double) nums.length / 2))];

      for (int first = 0, second = (nums.length - 1); first <= second; first++, second--) {
          if (nums[first] > nums[second]) {
              nexts[first] = nums[first];
          } else {
              nexts[first] = nums[second];
          }
          round++;
          System.out
                .println("Winner of round " + round + ": " + nexts[first]);
      } 

      if (nexts.length == 1) {
          return nexts[0];
      } else {
          return calcChamp(nexts);
      }
  }

  public static void main(String[] args) {
      new BattleofNumbers();
  }

}

数字之战

3 个答案: