你的程序有很多问题。
如果仅是想要实现，该论坛上有一个帖子，我给出了很完整的回复。
自己去找一下吧。

这是我帮你改好的：
#include <iostream.h>
#include <iomanip.h>
int prompt()
{
    int n;
    cout<<"Input a positive number,"<<endl
        <<"nonpositive will quit!"<<endl
        <<"=:";
    cin>>n;
    cin.delbuf();
    return n;
}

void main()
{
    int i,j,n;

    while((n=prompt())>0)
    {
        int **a=new int*[n];

        for(i=0;i<n;i++)
        {
            a[i] = new int[i+1];
            for(j=0;j<=i;j++)
            {
                if (j==i||j==0)
                    a[i][j]=1;
                else
                    a[i][j]=a[i-1][j]+a[i-1][j-1];
            }
        }
        for (i=0;i<n;i++)
        {
            for(j=0;j<=i;j++)
                cout<<setw(80/n)<<a[i][j];
            cout<<endl;
            delete[] a[i];
        }
        delete []a;
    }
}

//杨辉三角程序的C++实现
//作者：meteor135
//时间：2003.5.18
#include <iostream.h>
#include <iomanip.h>
int prompt()
{
    int n;
    cout<<"Input a positive number,"<<endl
        <<"nonpositive will quit!"<<endl
        <<"=:";
    cin>>n;
    cin.delbuf();
    return n;
}

void main()
{
    int i,j,n;

    while((n=prompt())>0)
    {
        int **a=new int*[n];

        for(i=0;i<n;i++)
        {
            a[i] = new int[i+1];
            a[i][i]=a[i][0]=1;//这里稍做修改
            for(j=1;j<i;j++)
            {
                a[i][j]=a[i-1][j]+a[i-1][j-1];
            }
        }
        for (i=0;i<n;i++)
        {
            for(j=0;j<=i;j++)
                cout<<setw(80/n)<<a[i][j];
            cout<<endl;
            delete[] a[i];
        }
        delete []a;
    }
}

[font=黑体][/font][size=5][/size][color=000080][/color]谢谢，谢谢-太谢谢了

[font=黑体]不客气！[/font]