`xgcd``a``b`procedureComputes the "extended greatest common divisor" of a and b, ie. it returns the two values x and y that constitute the solution of the equation

x*a + y*b = gcd(a, b)

`xgcd``a``b`procedureComputes the "extended greatest common divisor" of a and b, ie. it returns the two values x and y that constitute the solution of the equation

x*a + y*b = gcd(a, b)