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%%
%% 980202, 980311 Thom Fruehwirth, LMU
%% computes greatest common divisor of positive numbers written each as gcd(N)
%%
%% ported to hProlog by Tom Schrijvers

:- module(gcd,[]).

:- use_module( library(chr)).

:- constraints gcd/1.

gcd(0) <=> true.
%%gcd(N) \ gcd(M) <=> N=<M | L is M-N, gcd(L).
gcd(N) \ gcd(M) <=> N=<M | L is M mod N, gcd(L).  % faster variant

/*
%% Sample queries

gcd(2),gcd(3).

gcd(1.5),gcd(2.5).

X is 37*11*11*7*3, Y is 11*7*5*3, Z is 37*11*5,gcd(X),gcd(Y),gcd(Z).

*/