退步青年

var tools = {};
var salt = 'ac90f';

tools.generateHex = function(id){
    var hex = (id.toString(16)) + salt;
    hex = parseInt(hex,16);
    return hex.toString(32);
};

tools.decodeHex = function(hex){
    hex = parseInt(hex,32);
    hex = hex.toString(16);
   return hex.slice(0,hex.length - salt.length);
};