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Start your free trialStephen Cole
Courses Plus Student 15,809 PointsMy solution allows for negative numbers.
It doesn't seem to matter if the inputs are low/high or high/low. To allow for negative numbers, I added a test for the input to be >= 0
or <=0
.
I chose to output the results to the HTML.
Also, I put the prompt inside parseInt
to save a conversion step. I'm not lazy, I'm efficient. It looks similar but is, in fact, different. (No matter what my parents say.)*
// Access the DOM
const main = document.querySelector('main');
// Collect input from a user
const userInputLow = parseInt( prompt("Provide the low number:") );
const userInputHigh = parseInt( prompt("Provide the high number:") );
// If the low number is 0, it will test as false
// Added two conditions with a logical or to prevent this
if ( ( userInputLow <= 0 || userInputLow >= 0 ) && userInputHigh ) {
const randomNumber = Math.floor( Math.random() * ( userInputHigh - userInputLow + 1)) + userInputLow;
// Create a message displaying the random number
main.innerHTML = `
<h2>${randomNumber} is a random number between ${userInputLow} and ${userInputHigh}</h2>
`;
} else {
// userInput tested as false/NaN
main.innerHTML =
`<h2>Required inputs are numbers. Refresh the page and try again.</h2>`;
}
2 Answers
Steven Parker
231,124 PointsWhat if the low number was negative and the high number was 0?
Stephen Cole
Courses Plus Student 15,809 PointsOoo... good catch!
Fixed:
// Access the DOM
const main = document.querySelector('main');
// Collect input from a user
const userInputLow = parseInt( prompt("Provide the low number:") );
const userInputHigh = parseInt( prompt("Provide the high number:") );
// If the low number is 0, it will test as false
// Added two conditions with a logical or to prevent this
if ( ( userInputLow <= 0 || userInputLow >= 0 ) && ( userInputHigh <= 0 || userInputHight >=0 ) ) {
const randomNumber = Math.floor( Math.random() * ( userInputHigh - userInputLow + 1)) + userInputLow;
// Create a message displaying the random number
main.innerHTML = `
<h2>${randomNumber} is a random number between ${userInputLow} and ${userInputHigh}</h2>
`;
} else {
// userInput tested as false/NaN
main.innerHTML =
`<h2>Required inputs are numbers. Refresh the page and try again.</h2>`;
}
Steven Parker
231,124 PointsSteven Parker
231,124 PointsOK, one more suggestion. Instead of testing ranges that cover every possible number, check for not a non-number: