C++ Articles - Page 634 of 719

The inverse count of an array indicates how far or how close the array is from being sorted. If the array is already sorted, then the inverse count is zero, but if the array is sorted in reverse order, then the inverse count is maximum. Here we have given an integer array of size n and need to find the inversions in the array. If two array elements arr[i] and arr[j] form an inversion if arr[i]>arr[j] and i

In C++, Exception Handling is a process to handle runtime errors. Exception is an event which is thrown at runtime in C++. All exceptions are derived from std::exception class. It is a runtime error which can be handled. It prints exception message and terminates the program, if we don't handle the exception.Exceptions are defined in C++ standard as class that we can use inside our programs. The arrangement of parent-child class hierarchy has been shown below −Common exception classes in C++ are −Sr.No.Exception & Description1std::exceptionThis is an exception and parent class of all the standard C++ exceptions.2std::bad_castIt is an ... Read More

; is a C++ header that is included in C++11 or later versions and states the collection of types and functions to work with time. It is a part of the C++ Standard Template Library (STL). Why We Need It provides a precision-neutral concept by separating the durations and points of time. So, if we want to improve time over precision, we can use this library. provides three primary types of clocks: system_clock, steady_clock, and high_resolution_clock. These clocks are used to measure time in various ways: system_clock: It represents the system-wide real-time wall ... Read More

In this section we will see what is the RTTI (Runtime Type Information) in C++. In C++ the RTTI is a mechanism, that exposes information about an object’s datatype during runtime. This feature can be available only when the class has at least one virtual function. It allows the type of an object to be determined when the program is executing.In the following example the first code will not work. It will generate an error like “cannot dynamic_cast base_ptr (of type Base*) to type ‘class Derived*’ (Source type is not polymorphic)”. This error comes because there is no virtual function ... Read More

The fork() function creates a new process by duplicating the current one. It allows developers to perform parallel tasks and manage resources efficiently. When fork() is called, it returns a value. If the value is greater than 0, then it is in the parent process. Otherwise, it is in the child process. In this C++ article, we will learn how to use the fork() system call to perform calculations in parent and child processes.According to the problem statement, we will do calculations. So, in our parent process, we will find the sum of all even numbers in an array, and ... Read More

In this article, we implement a C++ program to print a hollow pyramid and diamond pattern. We can create solid Pyramid patterns easily using a loop. To make it hollow, we have to add a few logics. Hollow Pyramid A hollow pyramid is a pattern where a pyramid shape is formed, but only the outer edges (the borders) are filled with characters, while the interior is left empty. Let's explain how we can create hollow pyramid − The first line prints only one star (*). The last line (i.e., the ... Read More

std::reference_wrapper is a class template in C++ that allows you to store references to objects or functions in a way that makes them copyable and assignable. Normally, C++ references can't be stored in standard containers like std::vector or std::list, because references are not copyable. std::reference_wrapper solves this problem by internally storing a pointer to the referenced object. It acts like a wrapper around a reference and behaves almost like the original object. It can be passed to functions that take T& (a reference to T), because std::reference_wrapper is implicitly convertible to T&. This is especially useful when you ... Read More

The fork() system call is used to create a process commonly known as a child process if the fork() returns 0. Otherwise, the created process is known as the parent process. All processes created with fork() execute in parallel. But what if we want the last process to be executed first? In this case, the parent process would execute last because of bottom-to-top execution. This can be done using the wait() system call. The wait system call is used to process handling. It pauses the execution of the calling process until the child process has finished its execution. It's commonly ... Read More

In this article, we will see why we should avoid the std::endl while printing lines into the console or a file. We use std::endl to create a new line after the current line. For a few lines of I/O operations, it is not causing any problems. However, a large number of I/O tasks decreases performance. Why We Avoid Using std::endl There are the following reasons to avoid endl: The endl is used to create new lines, but it does not send to the new line only; after sending the cursor to the next line, it ... Read More

Here, we are going to learn how we can calculate the range of the different C++ data types such as signed data types (int, char, float, etc.) and unsigned data types (unsigned char, unsigned int, unsigned float, etc.). Calculating Range of Signed Data Types In C++, signed data types are used to represent both positive and negative integer values. So, to display their range, we use the following method − Calculate the total number of bits, multiply the sizeof bytes by 8. Calculate -2^(n-1) for minimum range ... Read More