完成 34 道题目

exercise-summary.txt

@@ -0,0 +1,249 @@
+toby@LAPTOP-GSIP3JR5:~/learning-cxx/exercises$ xmake run summary
+exercise00 testing
+==================
+[100%]: build ok, spent 0.044s
+Hello, InfiniTensor!
+=================
+exercise00 passed
+
+exercise01 testing
+==================
+[100%]: build ok, spent 0.044s
+0 + 0 = 0
+=================
+exercise01 passed
+
+exercise02 testing
+==================
+[100%]: build ok, spent 0.045s
+1 + 2 = 3
+=================
+exercise02 passed
+
+exercise03 testing
+==================
+[100%]: build ok, spent 0.044s
+befor func call: 99
+befor add: 99
+after add: 100
+after func call: 99
+=================
+exercise03 passed
+
+exercise04 testing
+==================
+[100%]: build ok, spent 0.045s
+=================
+exercise04 passed
+
+exercise05 testing
+==================
+[100%]: build ok, spent 0.04s
+fibonacci(20) = 6765
+fibonacci(20) = 6765
+=================
+exercise05 passed
+
+exercise06 testing
+==================
+[100%]: build ok, spent 0.045s
+=================
+exercise06 passed
+
+exercise07 testing
+==================
+[100%]: build ok, spent 0.045s
+fibonacci(90) = 2880067194370816120
+=================
+exercise07 passed
+
+exercise08 testing
+==================
+[100%]: build ok, spent 0.043s
+=================
+exercise08 passed
+
+exercise09 testing
+==================
+[100%]: build ok, spent 0.045s
+=================
+exercise09 passed
+
+exercise10 testing
+==================
+[100%]: build ok, spent 0.044s
+fibonacci(10) = 55
+=================
+exercise10 passed
+
+exercise11 testing
+==================
+[100%]: build ok, spent 0.033s
+fibonacci(10) = 55
+=================
+exercise11 passed
+
+exercise12 testing
+==================
+[100%]: build ok, spent 0.045s
+fibonacci(10) = 55
+=================
+exercise12 passed
+
+exercise13 testing
+==================
+[100%]: build ok, spent 0.043s
+fibonacci(10) = 55
+=================
+exercise13 passed
+
+exercise14 testing
+==================
+[100%]: build ok, spent 0.045s
+fibonacci(10) = 55
+=================
+exercise14 passed
+
+exercise15 testing
+==================
+[100%]: build ok, spent 0.045s
+=================
+exercise15 passed
+
+exercise16 testing
+==================
+[100%]: build ok, spent 0.046s
+=================
+exercise16 passed
+
+exercise17 testing
+==================
+[100%]: build ok, spent 0.045s
+1. X(1)
+2. A(2)
+3. A(1)
+4. X(3)
+5. B(1, X(3))
+
+-------------------------
+
+1. A(1)
+2. X(5)
+3. B(1, X(5))
+4. A(A const &) : a(1)
+5. ~B(1, X(5))
+6. ~X(5)
+7. ~A(1)
+
+-------------------------
+
+1. ~A(1)
+2. ~B(1, X(3))
+3. ~X(3)
+4. ~A(1)
+5. ~A(2)
+6. ~X(1)
+=================
+exercise17 passed
+
+exercise18 testing
+==================
+[100%]: build ok, spent 0.044s
+=================
+exercise18 passed
+
+exercise19 testing
+==================
+[100%]: build ok, spent 0.045s
+=================
+exercise19 passed
+
+exercise20 testing
+==================
+[100%]: build ok, spent 0.044s
+=================
+exercise20 passed
+
+exercise21 testing
+==================
+[100%]: build ok, spent 0.044s
+=================
+exercise21 passed
+
+exercise22 testing
+==================
+[100%]: build ok, spent 0.044s
+=================
+exercise22 passed
+
+exercise23 testing
+==================
+[100%]: build ok, spent 0.045s
+=================
+exercise23 passed
+
+exercise24 testing
+==================
+[100%]: build ok, spent 0.042s
+=================
+exercise24 passed
+
+exercise25 testing
+==================
+[100%]: build ok, spent 0.044s
+=================
+exercise25 passed
+
+exercise26 testing
+==================
+[100%]: build ok, spent 0.043s
+sizeof(std::vector<bool>) = 40
+=================
+exercise26 passed
+
+exercise27 testing
+==================
+[100%]: build ok, spent 0.044s
+=================
+exercise27 passed
+
+exercise28 testing
+==================
+[100%]: build ok, spent 0.042s
+=================
+exercise28 passed
+
+exercise29 testing
+==================
+[100%]: build ok, spent 0.041s
+=================
+exercise29 passed
+
+exercise30 testing
+==================
+[100%]: build ok, spent 0.045s
+=================
+exercise30 passed
+
+exercise31 testing
+==================
+[100%]: build ok, spent 0.043s
+=================
+exercise31 passed
+
+exercise32 testing
+==================
+[100%]: build ok, spent 0.033s
+=================
+exercise32 passed
+
+exercise33 testing
+==================
+[100%]: build ok, spent 0.044s
+=================
+exercise33 passed
+
+34/34 [##################################]
+warning: You are working in the project directory(/home/toby/learning-cxx) and you can also
+force to build in current directory via run `xmake -P .`
+toby@LAPTOP-GSIP3JR5:~/learning-cxx/exercises$ 

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;
     std::cout << x << " + " << x << " = " << x + x << std::endl;
     return 0;
 }

exercises/02_function/main.cpp

@@ -4,7 +4,7 @@
 // NOTICE: cppreference 中的示例中指出了复杂声明的解读法，建议认真阅读。
 // 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, int);
 
 int main(int argc, char **argv) {
     ASSERT(add(123, 456) == 123 + 456, "add(123, 456) should be 123 + 456");
@@ -15,5 +15,5 @@ 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 99");
     std::cout << "befor func call: " << arg << std::endl;
     func(arg);
-    ASSERT(arg == ?, "arg should be ?");
+    ASSERT(arg == 99, "arg should be 99");
     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 99");
     std::cout << "befor add: " << param << std::endl;
     param += 1;
-    ASSERT(param == ?, "param should be ?");
+    ASSERT(param == 100, "param should be 100");
     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

@@ -18,7 +18,7 @@ int main(int argc, char **argv) {
 
     // TODO: 观察错误信息，修改一处，使代码编译运行
     // PS: 编译运行，但是不一定能算出结果……
-    constexpr auto ANS_N = 90;
+    constexpr auto ANS_N = 20;
     constexpr auto ANS = fibonacci(ANS_N);
     std::cout << "fibonacci(" << ANS_N << ") = " << ANS << 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] ? 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;
     // TODO: 设置正确的循环条件
-    for (; false; ++cached) {
+    for (cached = 2; cached <= 90; ++cached) {
         cache[cached] = cache[cached - 1] + cache[cached - 2];
     }
     return cache[i];

exercises/08_pointer/main.cpp

@@ -5,6 +5,9 @@ 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]
+    for (int i = 0; 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

@@ -36,7 +36,7 @@ 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 +9,8 @@ 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];
+    for (cache.cached = 2; cache.cached <= 10; ++cache.cached) {
+        cache.cache[cache.cached] = cache.cache[cache.cached - 1] + cache.cache[cache.cached - 2];
     }
     return cache.cache[i];
 }
@@ -19,7 +19,7 @@ int main(int argc, char **argv) {
     // TODO: 初始化缓存结构体，使计算正确
     // 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;
+    FibonacciCache fib{{0, 1}};
     ASSERT(fibonacci(fib, 10) == 55, "fibonacci(10) should be 55");
     std::cout << "fibonacci(10) = " << fibonacci(fib, 10) << std::endl;
     return 0;