Example: Factorial Program
int
fac(int n) {
int x, a;
x = 1; a = 1;while( x <= n
) { a = a*x; x = x+1; }return a;}
The
state is the set of bindings to a, n, and x, which weÕll abbreviate (a, n, x), called the state vector.
Example:
(a, n, x): (1, 4, 1) -> (1, 4, 2) -> (2, 4, 3) -> (6, 4, 4) -> (24, 4, 5)
(a, n, x): (1, 4, 1) -> (1, 4, 2) -> (2, 4, 3) -> (6, 4, 4) -> (24, 4, 5)
24 is returned as fac(4)