Practice: Data Types and Arithmetic Operators

Try this exercise to practice writing statements using numbers, strings, and Boolean values. The code defines three variables (using the 'var' keyword) and uses assignment statements. Copy and paste the code into each program and run it to validate the output. You can use the Replit online editor at https://replit.com/languages/nodejs or any editor you choose. This exercise does not count towards your grade. It is just for practice!

Data Types

// This program demonstrates variables, literal constants, and data types.

var n;
var s;
var b;
    
n = 1.23456789012345;
s = "string";
b = true;
    
output("Number n = " + n);
output("String s = " + s);
output("Boolean b = " + b);

// Display output to the current environment
function output(text) {
  if (typeof document === 'object') {
    document.write(text);
  } 
  else if (typeof console === 'object') {
    console.log(text);
  } 
  else {
    print(text);
  }
}

Output

Number n = 1.23456789012345
String s = string
Boolean b = true

Discussion

Each code element represents:

// begins a comment
var n, s, and b define variables
; ends each line of JavaScript code
i = , d = , s =, b = assign literal values to the corresponding variables
output() calls the output function
function output(text) defines a output function that checks the JavaScript environment and writes to the current document, the console, or standard output as appropriate.