var three = require('three')
function build_blank(n) {
    var ret = "rgb("
    for (var i = 0; i < n; i++) {
        ret += " "
    }
    return ret + "";
}
var Color = three.Color
var time = Date.now();
new Color(build_blank(50000)) var time_cost = Date.now() - time;
console.log(time_cost + " ms")