js面试题

var num = 20;
var obj = {
    num: 30,
    fn: (function(num){
        this.num *= 3;
        num += 15;
        var num = 45;
        return function(){
            this.num *= 4;
            num += 20;
            console.log(num);
        }
    })(num)
}

var fn = obj.fn;
fn();
obj.fn();
console.log(num, obj.num);