36 lines
700 B
JavaScript
36 lines
700 B
JavaScript
/* eslint-disable no-var */
|
|
|
|
function Cyclist (size) {
|
|
if (!(this instanceof Cyclist)) return new Cyclist(size)
|
|
size = twoify(size)
|
|
this.mask = size - 1
|
|
this.size = size
|
|
this.values = new Array(size)
|
|
}
|
|
|
|
Cyclist.prototype.put = function (index, val) {
|
|
var pos = index & this.mask
|
|
this.values[pos] = val
|
|
return pos
|
|
}
|
|
|
|
Cyclist.prototype.get = function (index) {
|
|
return this.values[index & this.mask]
|
|
}
|
|
|
|
Cyclist.prototype.del = function (index) {
|
|
var pos = index & this.mask
|
|
var val = this.values[pos]
|
|
this.values[pos] = undefined
|
|
return val
|
|
}
|
|
|
|
module.exports = Cyclist
|
|
|
|
function twoify (n) {
|
|
if (n && !(n & (n - 1))) return n
|
|
var p = 1
|
|
while (p < n) p <<= 1
|
|
return p
|
|
}
|