完成作业

exercises/00_hello_world/main.cpp

@@ -6,6 +6,6 @@
 
 int main(int argc, char **argv) {
     // TODO: 在控制台输出 "Hello, InfiniTensor!" 并换行
-    std::cout : "Hello, InfiniTensor!" + std::endl;
+    std::cout << "Hello, InfiniTensor!" << std::endl;
     return 0;
 }

exercises/01_variable&add/main.cpp

@@ -5,6 +5,7 @@
 int main(int argc, char **argv) {
     // TODO: 补全变量定义并打印加法运算
     // x ?
+    int x = 1;
     std::cout << x << " + " << x << " = " << x + x << std::endl;
     return 0;
 }

exercises/02_function/main.cpp

@@ -5,7 +5,7 @@
 // NOTICE: 补充由内而外读法的机翻解释 <https://learn.microsoft.com/zh-cn/cpp/c-language/interpreting-more-complex-declarators?view=msvc-170>
 
 // TODO: 在这里声明函数
-
+int add(int a, int b);
 int main(int argc, char **argv) {
     ASSERT(add(123, 456) == 123 + 456, "add(123, 456) should be 123 + 456");
 
@@ -16,4 +16,5 @@ int main(int argc, char **argv) {
 
 int add(int a, int b) {
     // TODO: 补全函数定义，但不要移动代码行
+	return a+b;
 }

exercises/03_argument&parameter/main.cpp

@@ -8,19 +8,19 @@ void func(int);
 // TODO: 为下列 ASSERT 填写正确的值
 int main(int argc, char **argv) {
     auto arg = 99;
-    ASSERT(arg == ?, "arg should be ?");
+    ASSERT(arg == 99, "arg should be ?");
     std::cout << "befor func call: " << arg << std::endl;
     func(arg);
-    ASSERT(arg == ?, "arg should be ?");
+    ASSERT(arg == 99, "arg should be ?");
     std::cout << "after func call: " << arg << std::endl;
     return 0;
 }
 
 // TODO: 为下列 ASSERT 填写正确的值
 void func(int param) {
-    ASSERT(param == ?, "param should be ?");
+    ASSERT(param == 99, "param should be ?");
     std::cout << "befor add: " << param << std::endl;
     param += 1;
-    ASSERT(param == ?, "param should be ?");
+    ASSERT(param == 100, "param should be ?");
     std::cout << "after add: " << param << std::endl;
 }

exercises/04_static/main.cpp

@@ -10,10 +10,10 @@ static int func(int param) {
 
 int main(int argc, char **argv) {
     // TODO: 将下列 `?` 替换为正确的数字
-    ASSERT(func(5) == ?, "static variable value incorrect");
-    ASSERT(func(4) == ?, "static variable value incorrect");
-    ASSERT(func(3) == ?, "static variable value incorrect");
-    ASSERT(func(2) == ?, "static variable value incorrect");
-    ASSERT(func(1) == ?, "static variable value incorrect");
+    ASSERT(func(5) == 5, "static variable value incorrect");
+    ASSERT(func(4) == 6, "static variable value incorrect");
+    ASSERT(func(3) == 7, "static variable value incorrect");
+    ASSERT(func(2) == 8, "static variable value incorrect");
+    ASSERT(func(1) == 9, "static variable value incorrect");
     return 0;
 }

exercises/05_constexpr/main.cpp

@@ -12,7 +12,7 @@ constexpr unsigned long long fibonacci(int i) {
 }
 
 int main(int argc, char **argv) {
-    constexpr auto FIB20 = fibonacci(20);
+    auto FIB20 = fibonacci(20);
     ASSERT(FIB20 == 6765, "fibonacci(20) should be 6765");
     std::cout << "fibonacci(20) = " << FIB20 << std::endl;
 

exercises/06_array/main.cpp

@@ -11,13 +11,13 @@ unsigned long long fibonacci(int i) {
             return 1;
         default:
             // TODO: 补全三目表达式缺失的部分
-            return <condition> ? <cache> : (arr[i] = fibonacci(i - 1) + fibonacci(i - 2));
+            return arr[i] != 0 ? arr[i]  : (arr[i] = fibonacci(i - 1) + fibonacci(i - 2));
     }
 }
 
 int main(int argc, char **argv) {
     // TODO: 为此 ASSERT 填写正确的值
-    ASSERT(sizeof(arr) == ?, "sizeof array is size of all its elements");
+    ASSERT(sizeof(arr) == 720, "sizeof array is size of all its elements");
     // ---- 不要修改以下代码 ----
     ASSERT(fibonacci(2) == 1, "fibonacci(2) should be 1");
     ASSERT(fibonacci(20) == 6765, "fibonacci(20) should be 6765");

exercises/07_loop/main.cpp

@@ -5,9 +5,9 @@
 // READ: 纯函数 <https://zh.wikipedia.org/wiki/%E7%BA%AF%E5%87%BD%E6%95%B0>
 static unsigned long long fibonacci(int i) {
     // TODO: 为缓存设置正确的初始值
-    static unsigned long long cache[96], cached;
+    static unsigned long long cache[96]{0,1}, cached = 2;
     // TODO: 设置正确的循环条件
-    for (; false; ++cached) {
+    for (; cached <= i; ++cached) {
         cache[cached] = cache[cached - 1] + cache[cached - 2];
     }
     return cache[i];

exercises/08_pointer/main.cpp

@@ -5,6 +5,10 @@ bool is_fibonacci(int *ptr, int len, int stride) {
     ASSERT(len >= 3, "`len` should be at least 3");
     // TODO: 编写代码判断从 ptr 开始，每 stride 个元素取 1 个元素，组成长度为 n 的数列是否满足
     // arr[i + 2] = arr[i] + arr[i + 1]
+    int i = 0;
+    for(;i + 2 < len;i++){
+	    if(ptr[(i + 2)*stride] != ptr[i*stride] + ptr[(i + 1)*stride]) return false;
+    }
     return true;
 }
 

exercises/09_enum&union/main.cpp

@@ -37,7 +37,7 @@ ColorEnum convert_by_pun(Color c) {
 
     TypePun pun;
     // TODO: 补全类型双关转换
-
+    pun.c = c;
     return pun.e;
 }
 

exercises/10_trivial/main.cpp

@@ -9,8 +9,9 @@ struct FibonacciCache {
 
 // TODO: 实现正确的缓存优化斐波那契计算
 static unsigned long long fibonacci(FibonacciCache &cache, int i) {
-    for (; false; ++cached) {
-        cache[cached] = cache[cached - 1] + cache[cached - 2];
+    if(i <= cache.cached) return cache.cache[i];
+    for (; cache.cached <= i ; cache.cached++) {
+        cache.cache[cache.cached] = cache.cache[cache.cached - 1] + cache.cache[cache.cached - 2];
     }
     return cache.cache[i];
 }
@@ -20,6 +21,9 @@ int main(int argc, char **argv) {
     // NOTICE: C/C++ 中，读取未初始化的变量（包括结构体变量）是未定义行为
     // READ: 初始化的各种写法 <https://zh.cppreference.com/w/cpp/language/initialization>
     FibonacciCache fib;
+    fib.cache[0] = 0;
+    fib.cache[1] = 1;
+    fib.cached = 2;
     ASSERT(fibonacci(fib, 10) == 55, "fibonacci(10) should be 55");
     std::cout << "fibonacci(10) = " << fibonacci(fib, 10) << std::endl;
     return 0;

exercises/11_method/main.cpp

@@ -6,7 +6,7 @@ struct Fibonacci {
 
     // TODO: 实现正确的缓存优化斐波那契计算
     unsigned long long get(int i) {
-        for (; false; ++cached) {
+        for (; cached <= i; ++cached) {
             cache[cached] = cache[cached - 1] + cache[cached - 2];
         }
         return cache[i];
@@ -16,6 +16,9 @@ struct Fibonacci {
 int main(int argc, char **argv) {
     // TODO: 初始化缓存结构体，使计算正确
     Fibonacci fib;
+    fib.cache[0] = 0;
+    fib.cache[1] = 1;
+    fib.cached = 2;
     ASSERT(fib.get(10) == 55, "fibonacci(10) should be 55");
     std::cout << "fibonacci(10) = " << fib.get(10) << std::endl;
     return 0;

exercises/12_method_const/main.cpp

@@ -5,7 +5,8 @@
 struct Fibonacci {
     int numbers[11];
     // TODO: 修改方法签名和实现，使测试通过
-    int get(int i) {
+    int get(int i) const {
+	    return numbers[i];
     }
 };
 

exercises/13_class/main.cpp

@@ -15,13 +15,17 @@ class Fibonacci {
 public:
     // TODO: 实现构造器
     // Fibonacci()
-
+    Fibonacci(){
+	    this->cache[0] = 0;
+	    this->cache[1] = 1;
+	    this->cached = 2;
+    }
     // TODO: 实现正确的缓存优化斐波那契计算
     size_t get(int i) {
-        for (; false; ++cached) {
-            cache[cached] = cache[cached - 1] + cache[cached - 2];
+        for (;  this->cached <= i; ++(this->cached)) {
+            this->cache[this->cached] = this->cache[this->cached - 1] + this->cache[this->cached - 2];
         }
-        return cache[i];
+        return this->cache[i];
     }
 };
 

exercises/14_class_destruct/main.cpp

@@ -11,17 +11,25 @@ class DynFibonacci {
 
 public:
     // TODO: 实现动态设置容量的构造器
-    DynFibonacci(int capacity): cache(new ?), cached(?) {}
+    DynFibonacci(int capacity): cache(new size_t[capacity]), cached(capacity) {
+    cache[0] = 0;
+    cache[1] = 1;
+         for (int i = 2; i < capacity; ++i) {
+            cache[i] = cache[i - 1] + cache[i - 2];
+        }
+    }
 
     // TODO: 实现析构器，释放缓存空间
-    ~DynFibonacci();
+    ~DynFibonacci(){
+    delete[] cache;
+    }
 
     // TODO: 实现正确的缓存优化斐波那契计算
     size_t get(int i) {
-        for (; false; ++cached) {
-            cache[cached] = cache[cached - 1] + cache[cached - 2];
+        for (; this->cached <= i; ++this->cached) {
+            this->cache[this->cached] = this->cache[this->cached - 1] + this->cache[this->cached - 2];
         }
-        return cache[i];
+        return this->cache[i];
     }
 };
 

exercises/15_class_clone/main.cpp

@@ -10,17 +10,29 @@ class DynFibonacci {
 
 public:
     // TODO: 实现动态设置容量的构造器
-    DynFibonacci(int capacity): cache(new ?), cached(?) {}
+    DynFibonacci(int capacity): cache(new size_t[capacity]), cached(capacity) {
+    	cache[0] = 0;
+	cache[1] = 1;
+       for (int i = 2; i < capacity; ++i) {
+            cache[i] = cache[i - 1] + cache[i - 2];
+        }
+    }
 
     // TODO: 实现复制构造器
-    DynFibonacci(DynFibonacci const &) = delete;
+    DynFibonacci(DynFibonacci const & others): cache(new size_t[others.cached]), cached(others.cached){
+	for (int i = 0; i < cached; ++i) {
+            cache[i] = others.cache[i];
+        }
+    };
 
     // TODO: 实现析构器，释放缓存空间
-    ~DynFibonacci();
+    ~DynFibonacci(){
+    delete[] cache;
+    }
 
     // TODO: 实现正确的缓存优化斐波那契计算
     size_t get(int i) {
-        for (; false; ++cached) {
+        for (; cached <= i; ++cached) {
             cache[cached] = cache[cached - 1] + cache[cached - 2];
         }
         return cache[i];

exercises/16_class_move/main.cpp

@@ -7,29 +7,46 @@
 
 // READ: 移动构造函数 <https://zh.cppreference.com/w/cpp/language/move_constructor>
 // READ: 移动赋值 <https://zh.cppreference.com/w/cpp/language/move_assignment>
-// READ: 运算符重载 <https://zh.cppreference.com/w/cpp/language/operators>
-
+// READ: 运算符重载 <https://zh.cppreference.com/w/cpp/language/operators>)
 class DynFibonacci {
     size_t *cache;
     int cached;
 
 public:
     // TODO: 实现动态设置容量的构造器
-    DynFibonacci(int capacity): cache(new ?), cached(?) {}
+    DynFibonacci(int capacity): cache(new size_t[capacity]), cached(capacity) {
+    cache[0] = 0;
+    cache[1] = 1;
+    for(int i = 2;i < capacity;i++) cache[i] = cache[i-1]+cache[i-2];
+    }
 
     // TODO: 实现移动构造器
-    DynFibonacci(DynFibonacci &&) noexcept = delete;
+    DynFibonacci(DynFibonacci && other) noexcept : cache(other.cache), cached(other.cached){
+	    other.cache = nullptr;
+	    other.cached = 0;
+    };
 
     // TODO: 实现移动赋值
     // NOTICE: ⚠ 注意移动到自身问题 ⚠
-    DynFibonacci &operator=(DynFibonacci &&) noexcept = delete;
+    DynFibonacci &operator=(DynFibonacci && other) noexcept {
+    if(this != &other){
+	    delete[] cache;
+	    cache =other.cache;
+	    cached = other.cached;
+	    other.cache = nullptr;
+            other.cached = 0;
+    }
+    return *this;
+    }
 
     // TODO: 实现析构器，释放缓存空间
-    ~DynFibonacci();
+    ~DynFibonacci(){
+	    delete[] cache;
+    }
 
     // TODO: 实现正确的缓存优化斐波那契计算
     size_t operator[](int i) {
-        for (; false; ++cached) {
+        for (; cached<=i; ++cached) {
             cache[cached] = cache[cached - 1] + cache[cached - 2];
         }
         return cache[i];

exercises/17_class_derive/main.cpp

@@ -50,9 +50,9 @@ int main(int argc, char **argv) {
     B b = B(3);
 
     // TODO: 补全三个类型的大小
-    static_assert(sizeof(X) == ?, "There is an int in X");
-    static_assert(sizeof(A) == ?, "There is an int in A");
-    static_assert(sizeof(B) == ?, "B is an A with an X");
+    static_assert(sizeof(X) == 4, "There is an int in X");
+    static_assert(sizeof(A) == 4, "There is an int in A");
+    static_assert(sizeof(B) == 8, "B is an A with an X");
 
     i = 0;
     std::cout << std::endl
@@ -63,9 +63,9 @@ int main(int argc, char **argv) {
     // B ba = A(4);
 
     // 这也是不可能的，因为 A 是 B 的一部分，就好像不可以把套娃的外层放进内层里。
-    A ab = B(5);// 然而这个代码可以编译和运行！
-    // THINK: 观察打印出的信息，推测把大象放进冰箱分几步？
-    // THINK: 这样的代码是“安全”的吗？
+    A ab = B(5);// 然而这个代码可以编译和运行！因为这B是可以调用 A 的拷贝构造函数
+    // THINK: 观察打印出的信息，推测把大象放进冰箱分几步？构造B，拿到A的部分，析构B，构造A。
+    // THINK: 这样的代码是“安全”的吗？不安全，如果B重写了A的函数会出问题
     // NOTICE: 真实场景中不太可能出现这样的代码
 
     i = 0;