Number With Comma
function numberWithComma(number) {
// convert number to string
let str = String(number)
let s = ''
let count = 0
for (let i = str.length - 1; i >= 0; i--) {
s = str[i] + s
count++
// add a comma to every three numbers
if (count % 3 == 0 && i != 0) {
s = ',' + s
}
}
return s
}
// numberWithComma(111111)
// 111,111
// numberWithComma(123456789)
// 123,456,789