--description--
You can generate random decimal numbers with Math.random()
, but sometimes you need to generate random whole numbers. The following process will give you a random whole number less than 20
:
- Use
Math.random()
to generate a random decimal number. - Multiply that random decimal number by
20
. - Use
Math.floor()
to round this number down to its nearest whole number.
Remember that Math.random()
can never quite return a 1
, so it's impossible to actually get 20
since you are rounding down with Math.floor()
. This process will give you a random whole number in the range from 0
to 19
.
Putting everything together, this is what your code looks like:
Math.floor(Math.random() * 20);
You are calling Math.random()
, multiplying the result by 20, then passing the value to Math.floor()
to round the value down to the nearest whole number.
--instructions--
Use this technique to generate and return a random whole number in the range from 0
to 9
.
--hints--
The result of randomWholeNum
should be a whole number.
assert(
typeof randomWholeNum() === 'number' &&
(function () {
var r = randomWholeNum();
return Math.floor(r) === r;
})()
);
You should use Math.random
to generate a random number.
assert(__helpers.removeJSComments(code).match(/Math.random/g).length >= 1);
You should have multiplied the result of Math.random
by 10 to make it a number in the range from zero to nine.
assert(
__helpers.removeJSComments(code).match(/\s*?Math.random\s*?\(\s*?\)\s*?\*\s*?10[\D]\s*?/g) ||
__helpers.removeJSComments(code).match(/\s*?10\s*?\*\s*?Math.random\s*?\(\s*?\)\s*?/g)
);
You should use Math.floor
to remove the decimal part of the number.
assert(__helpers.removeJSComments(code).match(/Math.floor/g).length >= 1);
--seed--
--after-user-code--
(function(){return randomWholeNum();})();
--seed-contents--
function randomWholeNum() {
return Math.random();
}
--solutions--
function randomWholeNum() {
return Math.floor(Math.random() * 10);
}