Input and output using cin and cout in C++ - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to read an integer from the user using cin.

C++

#include <iostream>
using namespace std;

int main() {
    int number;
    cin [1] number;
    cout << "You entered: " << number << endl;
    return 0;
}

Drag options to blanks, or click blank then click option'

A>>

B<<

C>>=

D==

Attempts:

3 left

💡 Hint

Common Mistakes

Using << instead of >> with cin causes a syntax error.

Using == is a comparison, not input.

Using >>= is a bitwise operator, not for input.

The extraction operator for input with cin is >>. It reads data from the user into the variable.

2fill in blank

medium

Complete the code to print a message to the console using cout.

C++

#include <iostream>
using namespace std;

int main() {
    cout [1] "Hello, world!" << endl;
    return 0;
}

Drag options to blanks, or click blank then click option'

A>>

B<<

C==

D>>=

Attempts:

3 left

💡 Hint

Common Mistakes

Using >> instead of << with cout causes a syntax error.

Using == is a comparison, not output.

Using >>= is a bitwise operator, not for output.

The insertion operator for output with cout is <<. It sends data to the console.

3fill in blank

hard

Fix the error in the code to correctly read a floating-point number using cin.

C++

#include <iostream>
using namespace std;

int main() {
    float value;
    cin [1] value;
    cout << "Value: " << value << endl;
    return 0;
}

Drag options to blanks, or click blank then click option'

A<<

B=>

C==

D>>

Attempts:

3 left

💡 Hint

Common Mistakes

Using << instead of >> with cin.

Using == or => which are not input operators.

To read input with cin, use the extraction operator >>. Using << or other operators causes errors.

4fill in blank

hard

Fill both blanks to create a program that reads two integers and prints their sum.

C++

#include <iostream>
using namespace std;

int main() {
    int a, b;
    cin [1] a >> b;
    cout [2] "Sum: " << (a + b) << endl;
    return 0;
}

Drag options to blanks, or click blank then click option'

A>>

B<<

C==

D>>=

Attempts:

3 left

💡 Hint

Common Mistakes

Mixing up << and >> operators.

Using == instead of input/output operators.

Use >> to read input with cin and << to output with cout.

5fill in blank

hard

Fill all three blanks to read a string and an integer, then print them in a sentence.

C++

#include <iostream>
#include <string>
using namespace std;

int main() {
    string name;
    int age;
    cin [1] name >> age;
    cout [2] "Name: " << [3] << ", Age: " << age << endl;
    return 0;
}

Drag options to blanks, or click blank then click option'

A>>

Bname

C<<

D==

Attempts:

3 left

💡 Hint

Common Mistakes

Using == instead of input/output operators.

Forgetting to print the variable name.

Mixing up << and >> operators.

Use >> to read input, << to output, and the variable name to print the string.