What is cin in c++

cin is an input stream object in the C standard library, used to read data from the standard input (keyboard). Its syntax is: std::cin >> variable; can read different types of data, Such as integer, floating point number or string. cin will extract data until a whitespace character or end of file is encountered and store it in the specified variable. If the data types do not match, cin fails with the failbit set; use std::cin.fail() to check the failure status, and std::cin.ignore() to clear the input buffer.

cin in C

cin is an input stream in the C standard library Object that allows data to be read from the standard input device (usually the keyboard). It is the most common way to read data from the standard input stream std::cin.

Syntax:

<code class="cpp">std::cin >> variable;</code>

Usage:

• variable can be any data type (Such as int, float, char or string).
• Operator is used to extract data from the input stream and store it in a variable.
• The extraction operation will continue until a whitespace character (such as a space, tab, or newline character) is encountered or the end of the file.
• If the input data type does not match the variable's data type, cin will fail with its failbit bit set.

Example:

Read an integer:

<code class="cpp">int num;
std::cin >> num;</code>

Read a floating point number:

<code class="cpp">float value;
std::cin >> value;</code>

Note:

• cin Reads data from standard input, so it is affected by the system environment, such as redirections or pipes.
• If the input data is invalid or does not match, cin will fail. In this case, the failure status can be checked using the std::cin.fail() function.
• You must use the std::cin.ignore() function to clear the remaining characters in the input buffer to avoid read errors.

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