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Ekrem

Posted on • Updated on

# Calling a function on an array pair

``````function lcmCardinality(n) {
var factors = []
for (var i = 1; i <= n; i++) {
if (n % i == 0) {
factors.push(i)
}
}
var pairs = [].concat(
...factors.map((v, i) => factors.slice(i).map(w => v + ',' + w))
)
function gcd(x, y) {
if (typeof x !== 'number' || typeof y !== 'number') return false
x = Math.abs(x)
y = Math.abs(y)
while (y) {
var t = y
y = x % y
x = t
}
return x
}
function lcm(a, b) {
return (a / gcd(a, b)) * b
}
for (var i = 0; i < pairs.length; i++) {
var d = pairs[i]
var a = []
a.push(d)
var z = a.toString().split(',')
var result = z.map(function(x) {
return parseInt(x, 10)
})
for(var i=0;i<n;i++){
if(lcm(...result)==n){
console.log(lcm(...result))}};
}
}
``````

The code times out. I am having trouble getting the lcm(...result) where it equals n. Annie Hall

Hi, on the off chance this is still troubling you, here's the fix for the problems you're seeing:

When you're creating the pairs array, you're missing the "n, 1" pair. Therefore pairs is empty when n = 1 and you miss one of the lcm = 12 pairs when n = 12.
To fix this you can call the slice function with i as opposed to i+1

Additionally, while this won't affect your output as such, the for loop you use to iterate over pairs should read i < pairs.length. When i = pairs.length, then pairs[i] is undefined.
Then you can skip the handling steps of pairs[i] using variables a and d and directly assign z = pairs[i].split(",")

Hope that helps!

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