Create 6 kyu - Compile time #2 Ackermann function.cpp

freedan42x · Jul 18, 2022 · 1a0592f · 1a0592f
1 parent 0ea882b
commit 1a0592f
Showing 1 changed file with 25 additions and 0 deletions.
diff --git a/cpp/6 kyu - Compile time #2 Ackermann function.cpp b/cpp/6 kyu - Compile time #2 Ackermann function.cpp
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+typedef unsigned long long ull_t;
+
+template <int m, int n>
+struct ackermann
+{
+  enum : ull_t { value = ackermann<m - 1, ackermann<m, n - 1>::value>::value };
+};
+
+template <>
+struct ackermann<0, 0>
+{
+  enum : ull_t { value = 1 };
+};
+
+template <int n>
+struct ackermann<0, n>
+{
+  enum : ull_t { value = n + 1 };
+};
+
+template <int m>
+struct ackermann<m, 0>
+{
+  enum : ull_t { value = ackermann<m - 1, 1>::value };
+};