// file tree-tools.choc
// author : D Parigot
// date : 24.04.97

class main {

int fact (int n)
{

int h;
int s;

case this:

if (this.h == 0)
{

this.s = 1;

}
else [ show A as this ]
{

this.s = A.s * this.h;
A.h = this.h -1;

}

case fact:

this.h = n;
return this.s;

} // end fact

int fact (int n)
{

if (n == 0) fact = 1;
else [ show fact' as this ]
{

fact= fact'.fact * n;
fact'.n = n -1;

}

} // end fact

} // end class main