update: 添加题目

Signed-off-by: YdrMaster <[email protected]>

exercises/04_static/main.cpp

@@ -1,5 +1,3 @@
-// See <https://stackoverflow.com/questions/156767/whats-the-difference-between-an-argument-and-a-parameter>.
-
 #include <iostream>
 
 void func(int param) {

exercises/05_constexpr/main.cpp

@@ -1,5 +1,3 @@
-// See <https://stackoverflow.com/questions/156767/whats-the-difference-between-an-argument-and-a-parameter>.
-
 #include <iostream>
 
 constexpr int fibonacci(int i) {

exercises/06_loop/main.cpp

@@ -0,0 +1,15 @@
+#include <iostream>
+
+unsigned long long fibonacci(int i) {
+    static unsigned long long cache[128]{0, 1}, next = 2;
+    for (; next <= i; ++next) {
+        cache[next] = cache[next - 1] + cache[next - 2];
+    }
+    return cache[i];
+}
+
+int main(int argc, char **argv) {
+    auto fib100 = fibonacci(100);
+    std::cout << "fibonacci(100) = " << fib100 << std::endl;
+    return 0;
+}

exercises/07_struct/main.cpp

@@ -0,0 +1,25 @@
+#include <iostream>
+
+struct Fibonacci {
+    size_t cache[128];
+    int next = 2;
+
+    Fibonacci() : cache{0, 1}, next(2) {}
+    ~Fibonacci() {
+        std::cout << "Drop Fibonacci with next = " << next << std::endl;
+    }
+
+    size_t operator[](int i) {
+        for (; next <= i; ++next) {
+            cache[next] = cache[next - 1] + cache[next - 2];
+        }
+        return cache[i];
+    }
+};
+
+int main(int argc, char **argv) {
+    Fibonacci fib0, fib1;
+    std::cout << "fibonacci(10) = " << fib0[10] << std::endl;
+    std::cout << "fibonacci(100) = " << fib1[100] << std::endl;
+    return 0;
+}

exercises/08_class/main.cpp

@@ -0,0 +1,26 @@
+#include <iostream>
+
+class Fibonacci {
+    size_t cache[128];
+    int next = 2;
+
+public:
+    Fibonacci() : cache{0, 1}, next(2) {}
+    ~Fibonacci() {
+        std::cout << "Drop Fibonacci with next = " << next << std::endl;
+    }
+
+    size_t operator[](int i) {
+        for (; next <= i; ++next) {
+            cache[next] = cache[next - 1] + cache[next - 2];
+        }
+        return cache[i];
+    }
+};
+
+int main(int argc, char **argv) {
+    Fibonacci fib0, fib1;
+    std::cout << "fibonacci(10) = " << fib0[10] << std::endl;
+    std::cout << "fibonacci(100) = " << fib1[100] << std::endl;
+    return 0;
+}

xmake.lua

@@ -24,3 +24,15 @@ target("exercise04")
 target("exercise05")
     set_kind("binary")
     add_files("exercises/05_constexpr/main.cpp")
+
+target("exercise06")
+    set_kind("binary")
+    add_files("exercises/06_loop/main.cpp")
+
+target("exercise07")
+    set_kind("binary")
+    add_files("exercises/07_struct/main.cpp")
+
+target("exercise08")
+    set_kind("binary")
+    add_files("exercises/08_class/main.cpp")