第一次作业

QuestionA 打印方阵

import java.util.Scanner;

public class QuestionA {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        int x = scanner.nextInt();
        Print(Set(x));
        scanner.close();
    }
    public static int[][] Set(int x){
        int[][] a = new int[x][x];
        int number = 1;
        for (int i = 0; i < x; i++) {
            for(int j = 0;j < i; j++){
                a[j][i] = number++;
            }
            for(int k = i;k >= 0; k--){
                a[i][k] = number++;
            }
        }
        return a;
    }
    public static void Print(int[][] a){
        for(int[] array : a){
            for(int i = 0;i < array.length - 1; i++){
                System.out.print(array[i] + " ");
            }
            System.out.println(array[array.length - 1]);
        }
    }
}

QuestionB 个人所得税模拟计算

import java.util.Scanner;

public class QuestionB {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        double x = scanner.nextDouble();
        double result = 0;

        if(x <= 60000){result = 0;}
        else if(x > 60000 && x <= 100000){result = (x - 60000) * 0.03;}
        else if(x > 100000 && x <= 180000){result = 1200 + (x - 100000) * 0.1;}
        else if(x > 180000 && x <= 300000){result = 9200 + (x - 180000) * 0.18;}
        else if(x > 300000 && x <= 480000){result = 30800 + (x - 300000) * 0.25;}
        else if(x > 480000 && x <= 700000){result = 75800 + (x - 480000) * 0.3;}
        else if(x > 700000 && x <= 1000000){result = 141800 + (x - 700000) * 0.35;}
        else {result = 246800 + (x - 1000000) * 0.45;}

        System.out.print(String.format("%.2f",result));
        scanner.close();
    }
}

QuestionC 数字拼接

import java.util.Scanner;

public class QuestionC {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        int a = scanner.nextInt();
        int b = scanner.nextInt();
        //System.out.println(a);
        //System.out.println(b);

        int count1 = 1, count2 = 1;
        int num1 = a, num2 = b;
        while(num1 / 10 != 0){num1 /= 10;count1++;}
        while(num2 / 10 != 0){num2 /= 10;count2++;}
        //System.out.println(count1);
        //System.out.println(count2);

        int[] array1 = new int[count1];
        int[] array2 = new int[count2];
        for (int i = count1 - 1; i >= 0; i--) {
            array1[i] = a % 10;
            a /= 10;
        }
        for (int i = count2 - 1; i >= 0; i--) {
            array2[i] = b % 10;
            b /= 10;
        }
        /*
        for(int i : array1) System.out.print(i);
        System.out.println();
        for(int i : array2) System.out.print(i);
        System.out.println();
         */

        if(count1 >= count2){
            for(int i = 0;i < count2; i++){
                System.out.print(array1[i]);
                System.out.print(array2[i]);
            }
            for(int i = count2;i < count1; i++){
                System.out.print(array1[i]);
            }
        }
        else {
            for(int i = 0;i < count1; i++){
                System.out.print(array1[i]);
                System.out.print(array2[i]);
            }
            for(int i = count1;i < count2; i++){
                System.out.print(array2[i]);
            }
        }
        scanner.close();
    }
}

QuestionD 求解素数集合

import java.util.Scanner;

public class QuestionD {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        int n = scanner.nextInt(), count = 0;
        int[] array = new int[n];
        for (int i = 2; i <= n; i++) {
            if(judge(i)) array[count++] = i;
            else continue;
        }
        for(int i = 0; i < count - 1; i++) System.out.print(array[i] + " ");
        System.out.print(array[count - 1]);
    }
    public static boolean judge(int x){
        for (int i = 2; i < x; i++) {
            if(x % i == 0) return false;
            else continue;
        }
        return true;
    }
}

QuestionE 字符串去除并排序

import java.util.Scanner;

public class QuestionE {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        String s = scanner.nextLine();
        char[] charArray = s.toCharArray();
        int count = 0;
        for(int i = 0;i < charArray.length; i++){
            for(int j = i + 1;j < charArray.length; j++){
                if(charArray[i] == charArray[j]){
                    charArray[i] = '\0';
                    count++;
                }
                else if(charArray[i] > charArray[j]){
                    char c = charArray[i];
                    charArray[i] = charArray[j];
                    charArray[j] = c;
                }
            }
        }
        /*
        for(char i : charArray){
            System.out.print(i);
        }
        System.out.println();
        System.out.println(count);
         */
        char[] result = new char[charArray.length - count];
        count = 0;
        for(int i = 0;i < charArray.length; i++){
            if(charArray[i] != '\0') result[count++] = charArray[i];
            else continue;
        }
        for(char i: result) System.out.print(i);
    }
}