pointer

简明释义

英[ˈpɔɪntə(r)]美[ˈpɔɪntər]

n. 指针；指示器；教鞭；暗示

复 数 p o i n t e r s

英英释义

单词用法

同义词

反义词

例句

1.She tapped on the world map with her pointer.

她用教鞭轻点在那张世界地图上。

2.Move pointer to next element and return that object.

将指针移至下一个元素并返回该对象。

3.If you free an already freed pointer, it tells you.

如果您释放一个已经释放过的指针，它会告诉您。

4.Move the mouse pointer over the process diagram.

将鼠标指针移到流程图之上。

5.This is a pointer to environment data for the program.

是到此程序的环境数据的指针。

6.I need my laser pointer.

需要我的激光棒。

7.During tests over several days, the pointer or tracker tracked an IR source and directed a laser beam at that source.

在几天的测试中，指示器或跟踪器跟踪一个红外光源，并引导激光束击中目标。

8.It slows down nearly every pointer assignment.

减缓几乎每一个指针的分配。

9.The pointer on the compass always points north.

指南针上的指针总是指向北方。

10.In programming, a pointer is a variable that stores the address of another variable.

在编程中，指针是一个存储另一个变量地址的变量。

11.During the presentation, she used a laser pointer to highlight important information on the slides.

在演示过程中，她使用激光指示器突出幻灯片上的重要信息。

12.He pointed to the map with a pointer to show where they would be traveling.

他用指示器指向地图，展示他们将要旅行的地方。

13.The teacher gave the students a pointer on how to improve their writing skills.

老师给学生们提供了关于如何提高写作技巧的指示。

作文

In the realm of programming and computer science, the term pointer refers to a variable that stores the memory address of another variable. This concept is fundamental in languages like C and C++, where direct memory management is crucial for efficient performance. Understanding how pointers work can significantly enhance a programmer's ability to manipulate data structures and optimize algorithms.When we declare a pointer, we essentially create a reference that allows us to access and modify the value stored at a specific memory location. For instance, consider the following code snippet in C:cint main() { int var = 20; int *ptr = &var; // ptr is a pointer to var printf("Value of var: %d\n", *ptr); // Dereferencing the pointer return 0;}In this example, `ptr` is a pointer to the integer variable `var`. By using the address-of operator (&), we assign the address of `var` to `ptr`. To access the value of `var`, we use the dereference operator (*), which gives us the value stored at the address pointed to by `ptr`. This illustrates the power and flexibility of pointers in managing memory and data.Beyond basic usage, pointers are essential when it comes to dynamic memory allocation. Functions like `malloc` in C allow us to request memory from the heap, and the return value is a pointer to the allocated memory block. For example:cint *arr = (int*)malloc(10 * sizeof(int));Here, we allocate memory for an array of 10 integers and store the address of the first element in the pointer `arr`. This dynamic approach enables us to create data structures such as linked lists, trees, and graphs, which are pivotal in various algorithms and applications.However, with great power comes great responsibility. Improper handling of pointers can lead to issues like memory leaks and segmentation faults. A memory leak occurs when allocated memory is not properly deallocated, while a segmentation fault happens when a program tries to access a memory location that it shouldn't. Thus, understanding the lifecycle of a pointer—from allocation to deallocation—is vital for writing robust and efficient code.In addition to their application in programming, the concept of a pointer can be metaphorically applied in various fields. For instance, in education, a teacher may serve as a pointer to knowledge, guiding students toward understanding complex subjects. Similarly, in navigation, a compass acts as a pointer, helping travelers find their way. This broader interpretation of pointer highlights its significance beyond technical jargon, illustrating how it serves as a guide or reference in multiple contexts.In conclusion, the term pointer encapsulates both a technical and metaphorical significance. In programming, it is a powerful tool that facilitates efficient memory management and data manipulation. However, with this power comes the need for careful handling to avoid potential pitfalls. Understanding pointers not only enhances programming skills but also fosters a deeper appreciation for their role in guiding us through various aspects of life. As we continue to explore the digital landscape, mastering the concept of pointers will undoubtedly remain a valuable asset for aspiring programmers and tech enthusiasts alike.

在编程和计算机科学领域，术语pointer指的是一个存储另一个变量内存地址的变量。这个概念在C语言和C++等语言中是基本的，因为直接的内存管理对于高效性能至关重要。理解pointer的工作原理可以显著增强程序员操作数据结构和优化算法的能力。当我们声明一个pointer时，我们实质上创建了一个引用，使我们能够访问和修改存储在特定内存位置的值。例如，考虑以下C语言代码片段：cint main() { int var = 20; int *ptr = &var; // ptr是指向var的指针 printf("Value of var: %d\n", *ptr); // 解引用指针 return 0;}在这个例子中，`ptr`是指向整数变量`var`的pointer。通过使用取地址运算符（&），我们将`var`的地址分配给`ptr`。为了访问`var`的值，我们使用解引用运算符（*），它给我们提供了存储在`ptr`所指向地址的值。这展示了pointer在管理内存和数据方面的强大和灵活性。除了基本用法，pointer在动态内存分配中也是必不可少的。像C语言中的`malloc`函数允许我们从堆中请求内存，而返回值是指向已分配内存块的pointer。例如：cint *arr = (int*)malloc(10 * sizeof(int));在这里，我们为10个整数的数组分配内存，并将第一个元素的地址存储在pointer `arr`中。这种动态方法使我们能够创建链表、树和图等数据结构，这些在各种算法和应用中至关重要。然而，强大的功能也伴随着巨大的责任。不当处理pointer可能导致内存泄漏和段错误。内存泄漏发生在分配的内存没有被正确释放时，而段错误则发生在程序尝试访问不该访问的内存位置时。因此，理解pointer的生命周期——从分配到释放——对于编写健壮和高效的代码至关重要。除了在编程中的应用，pointer的概念也可以在多个领域进行比喻性应用。例如，在教育中，教师可以作为知识的pointer，引导学生理解复杂的学科。类似地，在导航中，指南针充当pointer，帮助旅行者找到方向。这种对pointer更广泛的解释突显了其在技术术语之外的重要性，说明它在多个上下文中作为指导或参考的作用。总之，术语pointer包含了技术和比喻上的重要意义。在编程中，它是一个强大的工具，促进高效的内存管理和数据操作。然而，这种力量需要小心处理，以避免潜在的陷阱。理解pointer不仅增强了编程技能，还培养了对其在生活各个方面引导我们角色的更深刻的欣赏。随着我们继续探索数字领域，掌握pointer的概念无疑将成为渴望成为程序员和技术爱好者的重要资产。