ackermann.cpp
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// RUN: %clang_cc1 -fsyntax-only -verify %s
// expected-no-diagnostics
// template<unsigned M, unsigned N>
// struct Ackermann {
// enum {
// value = M ? (N ? Ackermann<M-1, Ackermann<M, N-1> >::value
// : Ackermann<M-1, 1>::value)
// : N + 1
// };
// };
template<unsigned M, unsigned N>
struct Ackermann {
enum {
value = Ackermann<M-1, Ackermann<M, N-1>::value >::value
};
};
template<unsigned M> struct Ackermann<M, 0> {
enum {
value = Ackermann<M-1, 1>::value
};
};
template<unsigned N> struct Ackermann<0, N> {
enum {
value = N + 1
};
};
template<> struct Ackermann<0, 0> {
enum {
value = 1
};
};
int g0[Ackermann<3, 4>::value == 125 ? 1 : -1];