How to use cin in c++

cin is an input stream object in C, used to read data from standard input. Use the cin step: include header file . Use cin >> var to read data, where var is a variable.

Usage of cin in C

cin is an input stream object in C, which allows programs to start from standard Input (usually keyboard) reads data.

How to use cin

To use cin, you need to include the header file first. Data can then be read from standard input using the following syntax:

<code class="cpp">cin >> var;</code>

where:

• var is the variable from which the data is to be read.
• operator is the operator that reads data from the cin object.

For example, the following code reads an integer from standard input and stores it in the variable num:

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

Return type of cin

The cin operator returns an input stream object. If the read operation succeeds, it returns cin itself. If the read operation fails, it returns ios::failbit.

Common Errors

When using cin, you need to pay attention to the following common errors:

• Forgot to include the header file .
• Attempt to read data that does not match the variable type.
• Whitespace characters are not considered in string reading.
• Ignore newline characters, causing errors in subsequent read operations.

Example

The following code demonstrates the use of cin:

<code class="cpp">#include <iostream>

int main() {
    int age;
    std::string name;

    std::cout << "Enter your age: ";
    cin >> age;

    std::cout << "Enter your name: ";
    cin >> name;

    std::cout << "Age: " << age << ", Name: " << name << std::endl;

    return 0;
}</code>

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