dereference

问题 Is there a way to convert unsigned char array to float array without dereferencing each element of uchar array? unsigned char* arr1 = malloc(sizeof(unsigned char) * 3); float* arr2 = malloc(sizeof(float) * 3); *arr1 = 3; *(arr1 + 1) = 55; *(arr1 + 2) = 213; *arr2 = (float)(*arr1); // 3.0 *(arr2 + 1) = (float)(*(arr1 + 1)); // 55.0 *(arr2 + 2) = (float)(*(arr1 + 2)); // 213.0 来源： https://stackoverflow.com/questions/62136164/c-convert-unsigned-char-array-to-float-array

问题 Is there a way to convert unsigned char array to float array without dereferencing each element of uchar array? unsigned char* arr1 = malloc(sizeof(unsigned char) * 3); float* arr2 = malloc(sizeof(float) * 3); *arr1 = 3; *(arr1 + 1) = 55; *(arr1 + 2) = 213; *arr2 = (float)(*arr1); // 3.0 *(arr2 + 1) = (float)(*(arr1 + 1)); // 55.0 *(arr2 + 2) = (float)(*(arr1 + 2)); // 213.0 来源： https://stackoverflow.com/questions/62136164/c-convert-unsigned-char-array-to-float-array

问题 Is this behavior defined or not? volatile long (*volatile ptr)[1] = (void*)NULL; volatile long v = (long) *ptr; printf("%ld\n", v); It works because by dereferencing pointer to array we are receiving an array itself, then that array decaying to pointer to it's first element. Updated demo: https://ideone.com/DqFF6T Also, GCC even considers next code as a constant expression: volatile long (*ptr2)[1] = (void*)NULL; enum { this_is_constant_in_gcc = ((void*)ptr2 == (void*)*ptr2) }; printf("%d\n",

问题 Got this code (should be all that is relevant): //movable_ptr.hpp //Michal Cermak #ifndef MOVABLE_H #define MOVABLE_H template<typename T> class movable_ptr; template<typename T> class enable_movable_ptr { public: //default constructor enable_movable_ptr() {}; enable_movable_ptr(T* p) : ptr_(p) {}; //operators... T& operator*() const { return *ptr_; }; T* operator->() const { return ptr_; }; bool operator==(const enable_movable_ptr<T>& p) const { return p.ptr_ == ptr_; }; T* get() {return ptr

问题 Got this code (should be all that is relevant): //movable_ptr.hpp //Michal Cermak #ifndef MOVABLE_H #define MOVABLE_H template<typename T> class movable_ptr; template<typename T> class enable_movable_ptr { public: //default constructor enable_movable_ptr() {}; enable_movable_ptr(T* p) : ptr_(p) {}; //operators... T& operator*() const { return *ptr_; }; T* operator->() const { return ptr_; }; bool operator==(const enable_movable_ptr<T>& p) const { return p.ptr_ == ptr_; }; T* get() {return ptr

问题 I read different things on the Internet and got confused, because every website says different things. I read about * referencing operator and & dereferencing operator; or that referencing means making a pointer point to a variable and dereferencing is accessing the value of the variable that the pointer points to. So I got confused. Can I get a simple but thorough explanation about "referencing and dereferencing"? 回答1: Referencing means taking the address of an existing variable (using &) to

问题 I am trying to solve some Leetcode problems with Rust. However, I ran into some difficulties with LeetCode's TreeNode implementation. use std::cell::RefCell; use std::rc::Rc; // TreeNode data structure #[derive(Debug, PartialEq, Eq)] pub struct TreeNode { pub val: i32, pub left: Option<Rc<RefCell<TreeNode>>>, pub right: Option<Rc<RefCell<TreeNode>>>, } impl TreeNode { #[inline] pub fn new(val: i32) -> Self { TreeNode { val, left: None, right: None, } } } If I want to do an inorder traversal,

问题 I am trying to solve some Leetcode problems with Rust. However, I ran into some difficulties with LeetCode's TreeNode implementation. use std::cell::RefCell; use std::rc::Rc; // TreeNode data structure #[derive(Debug, PartialEq, Eq)] pub struct TreeNode { pub val: i32, pub left: Option<Rc<RefCell<TreeNode>>>, pub right: Option<Rc<RefCell<TreeNode>>>, } impl TreeNode { #[inline] pub fn new(val: i32) -> Self { TreeNode { val, left: None, right: None, } } } If I want to do an inorder traversal,

问题 As a Rust newbie, I'm working through the Project Euler problems to help me get a feel for the language. Problem 4 deals with palindromes, and I found two solutions for creating a vector of palindromes, but I'm not sure how either of them work. I'm using a vector of strings, products , that's calculated like this: let mut products = Vec::new(); for i in 100..500 { for j in 500..1000 { products.push((i * j).to_string()); } } For filtering these products to only those that are palindromic, I

问题 From what I understand (and please correct me if I'm wrong): int x, count = 10; int *hello; hello = &count; x = *hello; Here the variables x and count are declared to be of type integer. Additionally, the variable count is assigned the value of 10. hello is a pointer to type integer. hello is then assigned the address of count. In order to access the value of count, hello must have an asterisk in front of it, ie, *hello. So, x is assigned the value of whatever is in count and in this case, 10