java循环打印三角形基础题，麻烦帮我看看我的代码有什么问题，为什么跑不了

package book;
import java.util.Scanner;
public class Test5_19 {

public static void main(String[] args) {
    // TODO Auto-generated method stub
    Scanner in = new Scanner(System.in);
    System.out.println("enter the number of line");
    int numberOfLine = in.nextInt();

    for(int rows=1;rows<=numberOfLine;rows++){
        for(int space=numberOfLine-rows;space>=1;space++){
            System.out.print("  ");
        }
        for(int i=0;i<=numberOfLine-1;i++){
            int a = (int)(Math.pow(2, i));
            System.out.print(a+"  ");
        }
        for(int j=numberOfLine-1;j>=0;j--){
            int b = (int)(Math.pow(2, j));
            System.out.print(b+"  ");
        }
        System.out.println();
    }

}

}

 for(int space=numberOfLine-rows;space>=1;space++){ //初值为8，退出条件为小于1，但space一直在++，所以死循环

修改后的代码如下：

import java.util.Scanner;

public class Test5_19 {

    public static void main(String[] args) {

        Scanner in = new Scanner(System.in);
        System.out.println("enter the number of line");
        int numberOfLine = in.nextInt();

        for (int row = 0; row < numberOfLine; row++) {

            for (int space = 0; space < (numberOfLine - row - 1); space++)
                System.out.print("     ");


            for (int column = 0; column <= row; column++)
                print_val((int) Math.pow(2, column));


            for (int column = row - 1; column >= 0; column--)
                print_val((int) Math.pow(2, column));


            System.out.println();
        }

    }

    static void print_val(int n1) {  //不同位数打印不同空格
        if (n1 > 0 && n1 < 10)

            System.out.print("    ");
        else if (n1 > 9 && n1 < 100)

            System.out.print("   ");
        else
            // Print 2 spaces for other values
            System.out.print("  ");


        System.out.print(n1);

    }
}

考虑了输出格式，时间关系，没有加太多注释，您可以上机测试一下。

用心回答每个问题，如果对您有帮助，请采纳答案好吗，谢谢！

目测了一下，你不应该用空格， 而是应该用制表符（\t）

跑不了具体是什么情况

public class TestDemo {
public static void main(String[] args){
systemTrigon(8);
}

/* 随便输入你希望的值*/
private static void systemTrigon(int m){
int sum =1;
for (int i=1;i sum=sum*2;
}
int len= (sum+"").length();
int row = m;
int column=2*m-1;
int index = 1;
for (int i=0;i index = 1;
for (int j =0 ;j if (j System.out.printf(" "+getMString(len,"*")+" ");
}else if (j>(m+i-1)){
System.out.printf(" "+getMString(len,"*")+" ");
}else{
if (j<m){

                System.out.printf(" "+getMString(len,index+"")+" ");
                if (j<(m-1)){
                    index=index*2;
                }
            }else{
                index=index/2;;
                System.out.printf(" "+getMString(len,index+"")+" ");
            }

        }

    }
    System.out.println("");
}

}

/* 计算空格补位*/
private static String getMString(int len,String str){
int m = str.length();
int n = len-m;
StringBuffer stringBuffer = new StringBuffer();
for (int i=0;i<n;i++){
stringBuffer.append(" ");
}
stringBuffer.append(str);
return stringBuffer.toString();

}
}