Programming Articles - Page 2720 of 3366

Writing a Binary File To write a binary file in C/C++ use fwrite()/write() method. It is used to write a given number of bytes on the given stream, starting at the position of the "put" pointer. The file is extended if the put pointer is currently at the end of the file. If this pointer points into the middle of the file, characters in the file are overwritten with the new data. If any error has occurred during writing in the file, the stream is placed in an error state. Syntax of write() method Following is the basic syntax of ... Read More

fwrite() and fread() is used to write to a file in C.fwrite() syntaxfwrite(const void *ptr, size_t size, size_t nmemb, FILE *stream)whereptr - A pointer to array of elements to be writtensize - Size in bytes of each element to be writtennmemb - Number of elements, each one with a size of bytesstream – A pointer to a FILE object that specifies an output streamfread() syntaxfread(void *ptr, size_t size, size_t nmemb, FILE *stream)whereptr - A pointer to a block of memory with a minimum size of size*nmemb bytes.size - Size in bytes of each element to be read.nmemb - Number of ... Read More

To read a .so file in elf format, use readelfreadelf -Ws libName.soIt helps to extract symbol from binary.The standard tool used for listing all symbol is, nmnm -g libName.so

Listing files in a directory is used to write a program that opens a specified folder (e.g: "/myfiles"), reads its contents, and displays the names of each file and subfolder one by one. In C/C++, to see all the files in a directory, you can use special system functions that let you read the directory's contents. In real life, we open folder to see the contents inside the files. Similarly, in C or C++, we can write a program to display all the files and folders in a directory. Algorithm Following is the algorithm to get the list of files ... Read More

In C/C++, a null pointer is a special pointer that does not point to any valid memory location. Address 0 is used for Null Pointers because address 0 is reserved by the system, and it is guaranteed not to be used for valid data. So, when a pointer is assigned the value 0 (or nullptr), it means the pointer points to nothing. Some uses of null pointers are: To initialize a pointer variable when that pointer variable isn't assigned any valid memory address yet. To pass a null pointer to a function ... Read More

If a binary tree is traversed in-order, the left subtree is visited first, then the root and later the right sub-tree. The output the key in ascending order in in_order traversal. This is a C++ Program for Inorder Tree Traversal without Recursion.AlgorithmBegin      Function inOrder():       Declare a stack s.       Declare the current node as root.       While current node is not null and stack is not empty do          While current node is not null do             Push the current node on the ... Read More

An array is a collection of elements of the same type such as integers, string, etc. Array in STL In C++ Standard Template Library (STL) , we use std::array container to create arrays with a fixed size. the size cannot be changed once created. It works like a normal array but with extra features like knowing its own size and working with STL functions. Syntax Following is the syntax to create an array in C++ STL: array(data_type, size) array_name = {va1, val2, ...valn}; Here, data_type: It specifies the type of data array will accept. it can be any ... Read More

In C++, a vector is a dynamic array provided by the Standard Template Library (STL) that can grow or shrink in size and can store multiple elements of the same type (like int, string, etc.). Instead of accessing elements one by one using indexes like vec[0], vec[1], etc., The C++ provides helper functions like begin() and end() that return iterators. These iterators make it easy to loop through the vector from start to end, especially for loops. The vector::begin() Function The vector::begin() function returns an iterator pointing to the first element of the vector. Syntax vectorname.begin() Parameters This function does ... Read More

vector insert() function in C++ STL helps to increase the size of a container by inserting the new elements before the elements at the specified position.It is a predefined function in C++ STL.We can insert values with three types of syntaxes1. Insert values by mentioning only the position and value:vector_name.insert(pos, value);2. Insert values by mentioning the position, value and the size:vector_name.insert(pos, size, value);3. Insert values in another empty vector form a filled vector by mentioning the position, where the values are to be inserted and iterators of filled vector:empty_eector_name.insert(pos, iterator1, iterator2);AlgorithmBegin    Declare a vector v with values.    Declare ... Read More

unordered_multimap swap() function in C++ STL is used to swap the elements of one multimap to another of same size and type.AlgorithmBegin    Declaring two empty map container m, m1.    Insert some values in both m, m1 map containers.    Perform swap() function to swap the values of m, m1 map containers.    Printing the swapped values of m map container.    Printing the swapped values of m1 map container. End.Example Code Live Demo#include #include using namespace std; int main() {    unordered_map m, m1; // declaring m, m1 as empty map container    m.insert (pair('b', 10)); ... Read More