java学习p137

import java.util.Scanner;
public class a1 {
    public static void main(String[] args) {
        Scanner myScanner = new Scanner(System.in);
        System.out.print("请输入层数：");
        int totalLevel = myScanner.nextInt();
        for (int i = 1;i <= totalLevel;i++) {
            for (int k = 1;k <= totalLevel-i;k++) {
                System.out.print(" ");
            }
            for (int j = 1; j <= 2*i-1; j++) {
                System.out.print("*");
            }
            System.out.println("");
        }
    }
}

import java.util.Scanner;
public class a1 {
    public static void main(String[] args) {
        Scanner myScanner = new Scanner(System.in);
        System.out.print("请输入层数：");
        int totalLevel = myScanner.nextInt();
        for (int i = 1;i <= totalLevel;i++) {
            for (int k = 1;k <= totalLevel-i;k++) {
                System.out.print(" ");
            }
            for (int j = 1; j <= 2 * i - 1; j++) {
                if (j == 1 || j == 2 * i - 1 || i == totalLevel) {
                    System.out.print("*");
                }
                else {
                    System.out.print(" ");
                }
            }
            System.out.println("");
        }
    }
}

import java.util.Scanner;
public class a1 {
    public static void main(String[] args) {
        Scanner myScanner = new Scanner(System.in);
        System.out.print("请输入层数：");
        int totalLevel = myScanner.nextInt();
        for (int i = 1;i <= totalLevel;i++) {
            for (int k = 1;k <= totalLevel-i;k++) {
                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("");
        }
        int t = totalLevel - 1;
        for (int l = 1;l <= totalLevel - 1;l++) {
            for (int m = 1;m <= l;m++) {
                System.out.print(" ");
            }
            for (int n = 1; n <= 2 * t - 1; n++) {
                if (n == 1 || n == 2 * t - 1) {
                    System.out.print("*");
                }
                else {
                    System.out.print(" ");
                }
            }
            t--;
            System.out.println("");
        }
    }
}

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