java 如何打印/r 用java实现打印功能

利用java打印小图形

1、打印等腰三角形

import java.util.Scanner;

//打印等腰三角形
public class Test01 {
    public static void main(String[] args) {
        Scanner input = new Scanner(System.in);
        System.out.print("请输入等腰三角形的高：");
        int sum = input.nextInt();
        for(int i = 1; i <= sum; i++){
            for (int j = 0; j <= sum-i; j++){
                System.out.print(" ");
            }
            for (int k = 1; k <= 2*i-1; k++){
                System.out.print("*");
            }
            System.out.println();
        }
    }
}

2、打印空心等腰三角形

import java.util.Scanner;

//打印空心等腰三角形
public class Test02 {
    public static void main(String[] args) {
        Scanner input = new Scanner(System.in);
        System.out.print("请输入等腰三角形的高：");
        int sum = input.nextInt();
        for(int i = 1; i <= sum; i++){
            for (int j = 0; j <= sum-i; j++){
                System.out.print(" ");
            }
            for (int j = 1; j <= 2*i-1; j++){
                if (i == sum){  //打印最后一行
                    if (j % 2 != 0){   //为了美观，最后一行进行间隔性打印
                        System.out.print("*");
                    }else{
                        System.out.print(" ");
                    }
                }else{  //进行等腰三角形空心操作
                    if (j == 1 || j == 2*i-1){
                        System.out.print("*");
                    }else{
                        System.out.print(" ");
                    }
                }
            }
            System.out.println();
        }
    }
}

3、打印菱形

//由于菱形的打印条件限制，该代码只能实现奇数行的菱形

import java.util.Scanner;

//打印菱形
public class Test03 {
    public static void main(String[] args) {
        Scanner input = new Scanner(System.in);
        System.out.print("请输入菱形的高：");
        int sum = input.nextInt();
        if (sum % 2 == 0) {
            System.out.println("实际的菱形的高为: "+(sum+1));
        }else{
            System.out.println("实际的菱形的高为: "+ sum);
        }
        for(int i = 1; i <= sum/2+1; i++){
            for (int j = 0; j <= sum/2-i; j++){
                System.out.print(" ");
            }
            for (int j = 1; j <= 2*i-1; j++){
                System.out.print("*");
            }
            System.out.println();
        }
        for (int i = 1; i <= sum/2; i++) {
            for (int j = 0; j < i; j++) {
                System.out.print(" ");
            }
            for (int j = 0; j < 2*((sum/2+1)-i)-1; j++) {
                System.out.print("*");
            }
            System.out.println();
        }
    }
}

4、打印空心菱形

//由于菱形的打印条件限制，该代码也只能实现奇数行的菱形

import java.util.Scanner;

//打印空心菱形
public class Test04 {
    public static void main(String[] args) {
        Scanner input = new Scanner(System.in);
        System.out.print("请输入菱形的高：");
        int sum = input.nextInt();
        if (sum % 2 == 0) {
            System.out.println("实际的菱形的高为: "+(sum+1));
        }else{
            System.out.println("实际的菱形的高为: "+ sum);
        }
        for(int i = 1; i <= sum/2+1; i++){
            for (int j = 0; j <= sum/2-i; j++){
                System.out.print(" ");
            }
            for (int j = 1; j <= 2*i-1; j++){
                if (j == 1 || j == 2*i-1) {
                    System.out.print("*");
                }else{
                    System.out.print(" ");
                }
            }
            System.out.println();
        }
        for (int i = 1; i <= sum/2; i++) {
            for (int j = 0; j < i; j++) {
                System.out.print(" ");
            }
            for (int j = 1; j <= 2*((sum/2+1)-i)-1; j++) {
                if (j == 1 || j == 2*((sum/2+1)-i)-1) {
                    System.out.print("*");
                }else{
                    System.out.print(" ");
                }
            }
            System.out.println();
        }
    }
}

5、斐波那契数列

//斐波那契数列   1 1 2 3 5 8 13 21 34 55 89 144
    public static void main(String[] args) {
        int a = 1;
        int b = 1;
        System.out.print(a + " " + b + " ");
        int i = 1;
        while (i <= 10) {
            int c = a + b;
            System.out.print(c + " ");
            a = b;
            b = c;
            i++;
        }
    }

6、打印杨辉三角形

public class TestYangHui {

    //杨辉三角形
    public static void main(String[] args) {
        int[][] nums = new int[10][];
        //给杨辉三角形数组赋值
        for (int i = 0; i < nums.length; i++) {
            nums[i] = new int[i+1];
            for (int j = 0; j < nums[i].length; j++) {
                if (j == 0 || j == nums[i].length - 1){
                    nums[i][j] = 1;
                }else{
                    nums[i][j] = nums[i-1][j] + nums[i-1][j-1];
                }
            }
            System.out.println();
        }
        //遍历杨辉三角形数组
        for (int i = 0; i < nums.length; i++) {
            for (int j = 0; j <nums[i].length ; j++) {
                System.out.print(nums[i][j]+"\t");
            }
            System.out.println();
        }
    }
}