Practice: Data Types and Arithmetic Operators

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.