centralized performance resources

perf-cpp/scripts/ch11.cc

@@ -0,0 +1,48 @@
+/*
+   Write a constexpr function template with a non-type template parameter that
+   returns the factorial of the template argument. The following program should
+   fail to compile when it reaches factorial<-3>().
+
+   */
+
+template <int N>
+constexpr long long fibonacci() {
+  static_assert(N >= 0);
+  if constexpr (N <= 1) {
+    return N;
+  } else {
+    return fibonacci<N - 1>() + fibonacci<N - 2>();
+  }
+}
+
+// int main() {
+//   static_assert(fibonacci<1LL>() == 1);
+//   // static_assert(factorial<3>() == 6);
+//   // static_assert(factorial<5>() == 120);
+//
+//   // fibonacci<-3>();
+//
+//   return 0;
+// }
+
+#include <iostream>
+
+template <typename T>
+T add(T x, T y) {
+  return x + y;
+}
+
+template <typename T>
+T mult(T t, int N) {
+  return t * N;
+}
+
+int main() {
+  std::cout << add(2, 3) << '\n';
+  std::cout << add(1.2, 3.4) << '\n';
+
+  std::cout << mult(2, 3) << '\n';
+  std::cout << mult(1.2, 3) << '\n';
+
+  return 0;
+}