พีระมิดตัวเลข โดยใช้ลูปเดียว ด้วยภาษา C

#include<iostream.h>
#include<conio.h>
void main()
{
    clrscr();
    int i,j,k,l,n,x;
    cout<<"Please put number : ";
    cin>>n;
    i=j=k=l=1;
    x=2*n-1;
    while(x>=l)
    {
        if(i<=j) cout<<i<<" ";
        if(i==j)
        {
            cout<<"\n";
            if(k==1) j++;
            else j--;//k==0
            if(j==n) k=0;
            i=0;
            l++;
        }
        i++;
    }
    getch();
}

//Please put number : 5 
//1
//1 2
//1 2 3
//1 2 3 4
//1 2 3 4 5
//1 2 3 4
//1 2 3
//1 2 
//1