hashing/std:less on mpz

Andrey Vul andrey.vul at gmail.com
Thu Oct 8 07:43:35 CEST 2009

Is there a way to hash mpz types into a operator< -compatible way?
I want to memoize the Ackermann function by using std::map<pr,mpz_class>, where
struct pr { mpz_class x, y;
bool operator<(pr& o) {
if (x==0.x)
return y < o.y;
return x < o.x;

Is there a gmp function for comparing mpz to mpz?

Andrey Vul
andrey dot vul at gmail dot com
andrey dot vul at utoronto dot ca

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