Today I completed the content for week three, which included many commands, especially various string manipulations such as slicing, splitting, and formatting. Among them, creating a progress bar needs to be run in cmd, and I haven’t found a feasible method yet.In today’s exercises, I encountered a problem related to the Caesar cipher. This seemed … Read more
01 If there is an array int a[10];, the correct reference to the elements of the array a is A) a[10] B) a[3.5] C) a(5) D) a[10-10] Answer: D Explanation: For option A: Incorrect, the valid indices of the array are 0 to 9, a[10] is out of bounds and will lead to undefined behavior. … Read more
01 Observe the following statement: char str1[10], str2[10] = {“books”}; The correct statement that can assign the string “books” to the array str1 is A) str1 = {“Books”}; B) strcpy(str1, str2); C) str1 = str2; D) strcpy(str2, str1); Answer: B Explanation: For option A: Correct, using the standard library function to copy the string. For … Read more
String manipulation is commonly used in daily programming, such as searching, replacing, comparing, and inserting. Below, I will introduce some operations in the C++ environment that I can run on my machine. Searching using the function str.find() Replacing using str.replace(). Note that Chinese characters are three bytes. Comparing using str.compare() Inserting using str.insert() The above … Read more
String Handling in C: Common Functions and String Manipulation Techniques In C, strings are stored as arrays of characters, terminated by a null character (‘\0’). Although C does not have a built-in string type, we can manipulate strings using a series of functions from the standard library. This article will introduce some common string handling … Read more
Linux expr Command <span>expr</span> is a powerful command-line tool in Linux systems used for evaluating expressions, performing arithmetic operations, string manipulation, and logical comparisons. It is widely used in shell scripts for dynamic processing and value calculations. Although modern shells (like Bash) provide built-in arithmetic and string manipulation capabilities, <span>expr</span> still holds significant value due … Read more
📌 Problem Description Write a function str_replace that replaces the first occurrence of an old substring with a new substring in the given string, returning the modified new string. Requirements: Only a single replacement is required The returned new string must be dynamically allocated Example: Input: str="Hello World", old="World", new="C" Output: "Hello C" Difficulty: ⭐️ … Read more
#include <stdio.h> #include <string.h> #include <ctype.h> typedef void (*funcPtr)(char *); // 1. Remove leading and trailing whitespace (similar to Python's strip) void trim(char *str) { int i = 0, j; int len = strlen(str); // Remove leading whitespace while (isspace(str[i])) i++; // Remove trailing whitespace j = len – 1; while (j >= 0 && … Read more
String Operations in the C++ Standard Library In C++, strings are one of the most commonly used data types in our daily programming. The C++ Standard Library provides the <span>std::string</span> class to facilitate string manipulation. This article will detail how to use <span>std::string</span> for various basic string operations, including creation, access, modification, and querying. Creating … Read more
Previous Highlights:CMake Hello, WorldCMake VariablesCMake Official Tutorial (Basic Project Setup)CMake Official Tutorial (Library Creation)CMake Official Tutorial (Usage Requirements)CMake Official Tutorial (Installation and Testing)CMake Common Syntax (if Statements)CMake Common Syntax (Cache Variables)CMake Common Syntax (Environment Variables)CMake Common Syntax (Mathematical Calculations) In mainstream programming languages, strings are a fundamental and core data type, which is crucial, and … Read more