第004天作業(yè)改正: Craps賭博游戲

import java.util.Scanner;

//lang - language java核心包 自動(dòng)導(dǎo)入

// CoC - Convention over Configuration 約定優(yōu)于配置
public class CrapsGame {

    public static void main(String[] args) {
        Scanner input = new Scanner(System.in);
        int money = 1000;
        
        do {
            System.out.println("你的總資產(chǎn): " + money + "元.");
            int bet;
            do {
                System.out.print("請(qǐng)下注: ");
                bet = input.nextInt();
            } while (bet <= 0 || bet > money);
            // [min, max] - (int) (Math.random() * (max - min + 1)) + min);
            // [min, max) - (int) (Math.random() * (max - min)) + min);
            // (min, max) - (int) (Math.random() * (max - min)) + min + 1);
            // [50, 80] (80 - 50)  50   上限-下限 下限
            int face1 = (int) (Math.random() * 6 + 1);
            int face2 = (int) (Math.random() * 6 + 1);
            int firstPoint = face1 + face2;
            System.out.println("玩家搖出了" + firstPoint + "點(diǎn).");
            boolean needsGoOn = false;
            switch (firstPoint) {
            case 7:
            case 11:
                money += bet;
                System.out.println("玩家勝!");
                break;
            case 2:
            case 3:
            case 12:
                money -=bet;
                System.out.println("莊家勝!");
                break;
            default:
                needsGoOn = true;
            }
            while (needsGoOn) {
                face1 = (int) (Math.random() * 6 + 1);
                face2 = (int) (Math.random() * 6 + 1);
                int currentPoint = face1 + face2;
                System.out.println("玩家搖出了" + currentPoint + "點(diǎn).");
                if (currentPoint == 7) {
                    money -= bet;
                    System.out.println("莊家勝!");
                    needsGoOn = false;
                } else if (currentPoint == firstPoint) {
                    money += bet;
                    System.out.println("玩家勝!");
                    needsGoOn = false;
                }
            } 
        } while (money > 0);
        System.out.println("你已經(jīng)破產(chǎn)!");
        input.close();
    }
}

練習(xí)

• 1.輸出如下:
  1 1
  2 4
  3 9
  ... ...
  10 100

        for (int i = 1; i <= 100; i++) {
            //  \t 表示制表符 嗡呼， 每列左對(duì)齊
            System.out.println(i + "\t" + i * i);
            
            // 不夠x位 左邊補(bǔ) 空格 右對(duì)齊
            System.out.printf("%3d %5d\n", i, i * i); 
            
            // 補(bǔ)0
            System.out.printf("%03d %05d\n", i, i * i); 
        }

• 2.輸入一個(gè)正整數(shù)抽减，判斷是不是素?cái)?shù)
  提示：檢查2~(n - 1)之間有沒有n的因子

        Scanner input = new Scanner(System.in);
        System.out.print("請(qǐng)輸入一個(gè)數(shù): ");
        int n = input.nextInt();
        boolean isPrime = true; // 先假設(shè)n是素?cái)?shù)
        for (int i = 2; i <= n-1; ++i) {
            if (n % i == 0) {
                isPrime = false;
                break;
            } 
        }
        System.out.println(n + (isPrime ? "是" : "不是") +"素?cái)?shù)");
        input.close();

• 3.把1~100之間的所有素?cái)?shù)打印出來

public class Ex03 {

    public static boolean isPrime(int i) {
        for (int j = 2; j <= Math.sqrt(i); j++) {
            if (i % j == 0) {
                return false;
            }
        }
        return true;
    }
    
    public static void main(String[] args) {
        for (int i = 1; i <= 100 ; i++) {
            /*boolean isPrime = true;
            for (int j = 2; j <= Math.sqrt(i); j++) {
                if (i % j == 0) {
                    isPrime = false;
                    break;
                }
            }
            if (isPrime) {
                System.out.println(i);  
            }*/
            if (isPrime(i)) {
                System.out.println(i);      
            }
        }
    }
}

• 4.打印乘法口訣表

        for (int i = 1; i <= 9; i++) {
            for (int j = 1; j <= i; j++) {
                //System.out.printf("%d * %d = %2d   ", j, i, i * j);
                System.out.printf("%d*%d=%d\t", j, i, i * j);
                //System.out.print(j + "*" + i + "=" + j * i + "\t");
            }
            System.out.println("");
        }

• 5.猴子吃桃子
  第一天 吃所有桃子的一半 多吃一個(gè)
  第二天 吃剩下桃子的一半 多吃一個(gè)
  ...
  第十天 每吃 只有 1 個(gè)
  算總共多少桃子

        int total = 1;
        for (int i = 9; i >= 1; i--) {
            total = (total + 1) * 2;
        }
        System.out.println(total);
    }

• 6.百錢百雞
  公雞 5塊一只 母雞 3塊一只 小雞一塊買3只
  100塊買100只雞
  公雞坡慌、母雞多艇、小雞各有多少只

        // 窮舉法  - 窮盡所有的可能性直到找到正確答案
        for (int i = 0; i <= 100 / 5; i++) {
            for (int j = 0; j <= 100 / 3; j++) {
                for (int k = 0; k <= 99; k += 3) {
                    if (5 * i + 3 * j + k / 3 == 100 && i + j + k == 100) {
                        System.out.printf("公雞有%d只趁冈，母雞有%d只，小雞有%d只\n",
                                i, j, k);
                    }
                }
            }
        }
        //
        for (int x = 0; x <= 20; x++) {
            for (int y = 0; y <= 33; y++) {
                int z = 100 - x - y;
                if (5 * x + 3 * y + z / 3 == 100 && z % 3 == 0) {
                    System.out.printf("公雞有%d只血巍，母雞有%d只萧落，小雞有%d只\n",
                            x, y, z);
                }
            }
        }

• 7.完美數(shù)
  6 = 1 + 2 + 3
  28 = 1 + 2 + 7 + 14
  找1~10000 之間的完美數(shù)

        for (int i = 2; i <= 10000; i++) {
            int sum = 1;
            for (int j = 2; j <= Math.sqrt(i); j++) {
                if (i % j == 0) {
                    sum += j;
                    if (i / j != j) {
                        sum += i / j;
                    }
                }
            }
            if (sum == i) {
                System.out.println(i);  
            }
        }

• 8.輸入年月日嚎幸，告訴這是這年的第幾天

        import java.util.Scanner;

    // 輸入年月日颜矿，告訴這是這年的第幾天
public class Ex10 {

    //如果程序中出現(xiàn)了重復(fù)的或相對(duì)獨(dú)立的功能 那么應(yīng)該將這些功能單獨(dú)寫出一個(gè)方法
    public static boolean isLeapYear(int year) {
        return year % 4 == 0 && year % 100 != 0 || year % 400 == 0;
    }
    
    public static int daysOfMonth(int year, int month) {
        if (month == 2) {
            if (isLeapYear(year)) {
                return 29;
                }
            else {
                return 28;
            }
        }
        else if (month == 4 || month == 6 || month == 9 || month == 11) {
            return 30;
            }
        else {
            return 31;
        }
    }
    
    public static void main(String[] args) {
        Scanner input = new Scanner(System.in);
        System.out.print("請(qǐng)輸入年、月鞭铆、日: ");
        int year = input.nextInt();
        int month = input.nextInt();
        int day = input.nextInt();
        int days = 0;
        
        for (int i = 1; i < month; i++) {
            /*
            switch (i) {
            case 4: case 6: case 9: case 11:
                days += 30;
                break;
            case 2: 
                if (year % 4 == 0 && year % 100 != 0 || year % 400 == 0) {
                    days += 29;
                }
                else {
                    days += 28;
                }
                break;
            default:
                days +=31;
                break;
            }
            */
            days += daysOfMonth(year, i);
        }
        days += day;
        //System.out.println("這天是這一年的第" + days + "天");
        System.out.printf("%d年%d月%d日是這一年的第%d天.", year, month, day, days);
        input.close();
    } }

作業(yè)

• **1.輸出如下各種圖形:

1.png

    for (int i = 1; i <= 5; i++) {
        for (int j = 1; j <= i; j++) {
            System.out.print("*");
        }
        System.out.println();
    }
    
    for (int i = 1; i <= 5; i++) {
        for (int j = 5; j >= 1; j--) {
            if (j > i) {
                System.out.print(" ");
            }
            else {
                System.out.print("*");
            }
        }
        for (int j = 4; j >= i; j--) {
            System.out.print(" ");
        }
        for (int k = 1; k <= i; k++) {
            System.out.print("*");  
        }
        System.out.println();
    }
    
    
    for (int i = 1; i <= 5; i++) {
        for (int j = 4 - i; j >= 0; j--) {
            System.out.print(" ");
        }
        for (int k = i * 2 - 1; k > 0; k--) {
            System.out.print("*");  
        }
        System.out.println();
    }

• 2. 5個(gè)人去打魚或衡，打了很多魚
  a、b车遂、c封断、d、e
  a 先醒過來舶担，分5份坡疼，多了一條，扔掉衣陶，拿走自己的一份
  b 然后醒過來柄瑰，分5份，多了一條剪况，扔掉教沾，拿走自己的一份
  ...
  最少要捕多少魚
  public class Test01 {

   public static void main(String[] args) {
    int fish = 1;
    boolean flag = true;
    do {
        int fish2 = fish;
        for (int i = 1; i <= 5; i++) {
            if (fish2 % 5 == 1) {
                fish2 -= myOwn(fish2) + 1;  
            }
            else {
                break;
            }
            if (i == 5) {
                flag = false;
            }
        }
        fish += 1;
    } while (flag);
    System.out.println("最少要捕: " + (fish - 1) + "條魚");
  }
  public static int myOwn(int fish) {
    return (fish - 1) / 5;
  }
  }
  

• 3.2個(gè)日期差多少天

   public class Ex11 {
  
    public static void main(String[] args) {
    Scanner input = new Scanner(System.in);
    System.out.print("請(qǐng)輸入第一個(gè)日期的年、月译断、日: ");
    int year1 = input.nextInt();
    int month1 = input.nextInt();
    int day1 = input.nextInt();
    System.out.print("請(qǐng)輸入第二個(gè)日期的年授翻、月、日: ");
    int year2 = input.nextInt();
    int month2 = input.nextInt();
    int day2 = input.nextInt();
    int total = 0;
    
    if (year1 == year2) {
        total += theSameYearDifferenceBetweenMonth(year1, month1,
                day1, month2, day2);
    }
    else if (year1 < year2) {
        total += smallYearBigYearOfDays(year1, month1, day1,
                year2, month2, day2);
    }
    else {
        total += smallYearBigYearOfDays(year2, month2, day2,
                year1, month1, day1);
    }
    
    System.out.printf("%d年%d月%d日和%d年%d月%d日相差了%d天.", 
            year1, month1, day1, year2, month2, day2 , total);
    input.close();
  }
  
  public static boolean isLeapYear(int year) {
    return year % 4 == 0 && year % 100 != 0 || year % 400 == 0;
  }
  
  public static int daysOfMonth(int year, int month) {
    int days;
    switch (month) {
    case 2:
        days=isLeapYear(year) ? 29 : 28;
        break;
    case 4: case 6: case 9: case 11:
        days = 30;
        break;
    default:
        days = 31;
        break;
    }
    return days;
  }
  
  public static int daysOfYear(int year) {
    return isLeapYear(year) ? 366 : 365;
  }
  
  public static int theSameYearDifferenceBetweenMonth(int year, int month1,
        int day1, int month2,int day2 ) {
    int total = 0;
    if (month1 == month2) {
        if (day1 >= day2) {
            total += day1 - day2;
        } else {
            total += day2 - day1;
        }
    }
    else if (month1 < month2) {
        for (int i = month1 + 1; i < month2; i++) {
            total += daysOfMonth(year, i);
        }
        total +=  daysOfMonth(year, month1) - day1 + day2; 
    }
    else {
        for (int i = month2 + 1; i < month1; i++) {
            total += daysOfMonth(year, i);
        }
        total += daysOfMonth(year, month2) - day2 + day1;
    }
    return total;
  }
  
  public static int smallYearBigYearOfDays(int year1, int month1, int day1,
        int year2, int month2, int day2) {
    int total = 0;
    for (int i = year1 + 1; i < year2; i++) {
        total += daysOfYear(i);
    }
    if (month1 < 12) {
        total += theSameYearDifferenceBetweenMonth(year1, month1, day1,
                12, 31);
    }
    else {
        total += daysOfMonth(year1, month1) - day1;
    }
    if (month2 > 1) {
        total += theSameYearDifferenceBetweenMonth(year2, 1, 1, month2, day2);
    }
    else {
        total += day2;
    }
    return total + 1;
  }
  }