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JavaScript JavaScript Basics (Retired) Creating Reusable Code with Functions Random Number Challenge Solution

Posted by STEVEN AGUILAR
STEVEN AGUILAR
6,336 Points

How can I make this so that variables defined by prompts set the numbers? 

var L = prompt("Pick a number less than 100");
var U = prompt("Pick a number greater than 100");

function randomNumber(U, L){
return Math.floor(Math.random() * (U - L + 1)) + L
}

alert(randomNumber(U,L));

2 Answers

andren
andren
28,558 Points
andren
andren
28,558 Points

You can use the parseInt function which will convert a string (which is what the prompts return) into an int. Like this:

var L = parseInt(prompt("Pick a number less than 100"));
var U = parseInt(prompt("Pick a number greater than 100"));
STEVEN AGUILAR
STEVEN AGUILAR
6,336 Points
STEVEN AGUILAR
STEVEN AGUILAR
6,336 Points

I see so the problem was that I didn't convert the numbers to an integer?

andren
andren
28,558 Points
andren
andren
28,558 Points

Yes. For JavaScript to treat something as a number it has to be stored as an integer. Numbers stored in strings are treated as text. Some operators like + performs one action on strings (concatenation) and a different one on numbers (addition). So when performing math operations it's important that the variable is stored as the correct type.