@ johnny1208 :
老兄，为了完成您布置的作业，昨晚花了一晚上，今天早晨又折腾了一上午，终于搞定了。

[quote]
          1
        1   1
      1   2   1
    1   3   3   1
  1   4   6   4   1
1   5   10  10  5   1
     。。。。。。
上面这个是杨辉三角，要打印他很简单，用个2唯数组写个百把十句就OK了。但要是限定只允许你使用循环嵌套做，你不会数学原理能行吗？所以代数还是很重要滴，不学是不行滴。[/quote]

问题出处：http://www.programfan.com/club/showbbs.asp?id=47781

这是我的小程序：

#include <iostream>
#include <stdio.h>

using namespace std;

// define function prototype
void yhtriangle(int& x);

int main()
{
    int lines;
            
    cout<<"This is a little prog to print YangHui triangle ."<<endl;
    cout<<"Please enter the lines what you want to print: "<<endl;
    cin>>lines;
    
    yhtriangle(lines);
    
    cout<<endl<<endl<<endl;

    system("pause");

    return 0;
        
}

void yhtriangle(int& x)
{
    
    int *yanghui;
         int *temp;       //to save operation value.   

    int n;          
    int blank;      //counter the space numbers
    int counter;
        
    //cin>>x;       // I decide to input x from main()
    
    //make two dynamic arrays
    yanghui = new int[x];
    temp = new int[x];
    
    //initialize arrayes
    
    for(n = 0; n < x; n++)
    {
        yanghui[n] = 0;
        temp[n] = 0;
       }
       
         yanghui[0] = 1;  
         temp[0] = 1;
       blank = x;

    //circulate print triangle
    for(counter = 0; counter < x; counter++)
    {
        for(n = 0; n < blank; n++)
            cout<<" ";            
        for(n = 0; n < counter; n++)
        {
            yanghui[n+1]=temp[n+1]+temp[n];    
            cout<<yanghui[n]<<" "<<flush;
                      temp[n] = yanghui[n];
        }
                                
        cout<<endl;
        blank--;
    }
    delete new int[x];   //release dynamic array's memory.

}

程序运行正常，但打出的三角形不美观，希望大家帮忙改进。