要求控制台打印出
     *
    * *
   * * *
  * * * *
 * * * * *

#include<stdio.h>
int main()
{
    char m='*';
   printf("%6c\n%5c%2c\n%4c%2c%2c\n%3c%2c%2c%2c\n%c%2c%2c%2c%2c\n"
                                   ,m,m,m,m,m,m,m,m,m,m,m,m,m,m,m);


}

用JAVA代码实现

public class Triangle {

    public static void main(String[] args) {
        printTriangle(5);
    }

    public static void printTriangle(int line) {
        for (int i = 0 ;i <= line ;i++) {
            for (int j = 0; j < line - i; j++)
            {
                System.out.print(" ");
            }

            for (int x = 0;x < 2*i-1; x++ )
            {
                if(x%2==0)
                System.out.print("*");
                else
                    System.out.print(" ");
            }
            System.out.println();
        }
    }
}