Flash cards
Review the key moves
What is the main idea behind C++ User Input?
Lesson checks
Practice each idea before moving on
Short Mimo-style checks built from this lesson's code, terms, and sequence.
Which statement best captures the main point of this lesson?
Complete the missing token from the example code.
___ << "Type a number: "; // Type a number andPut the learning moves in the order that makes the concept easiest to apply.
You have already learned that cout is used to output (print) values. Now we will use cin to get user input.
cin is a predefined variable that reads data from the keyboard with the extraction operator ( >> ).
In the following example, the user can input a number, which is stored in the variable x . Then we print the value of x :
Example
int x;
cout << "Type a number: "; // Type a number and
press enter
cin >> x; // Get user
input from the keyboard
cout << "Your number is: " << x;
// Display the input valuecout is pronounced "see-out". Used for output , and uses the insertion operator ( << )
cin is pronounced "see-in". Used for input , and uses the extraction operator ( >> )
Creating a Simple Calculator
In this example, the user must input two numbers. Then we print the sum by calculating (adding) the two numbers:
Example
int x, y;
int sum;
cout << "Type a number: ";
cin >> x;
cout << "Type another number: ";
cin >> y;
sum = x + y;
cout << "Sum is: " << sum;There you go! You just built a basic calculator!