迅雷的两题，可以，很简单

	/*请完成下面这个函数，实现题目要求的功能
******************************开始写代码******************************/
function EventEmitter() {
    var onEvents = {}, onceEvents = {};
    this.on = function(event, listener){
        if (event in onEvents) {
            onEvents[event].push(listener);
        } else {
            onEvents[event] = [listener];
        }
    };
    this.once = function(event, listener){
        if (event in onceEvents) {
            onceEvents[event].push(listener);
        } else {
            onceEvents[event] = [listener];
        }
    };
    this.emit = function(event, ...args){
        var onList = onEvents[event],
            onceList = onceEvents[event];
        if (onList)
            for (var i in onList)
                onList[i].apply(null, args);
        if (onceList) {
            for (var i in onceList)
                onceList[i].apply(null, args);
            delete onceEvents[event];
            //onceEvents[event].length = 0;//清空once的***
        }
        
    };
    this.remove = function(event, listener){
        var onList = onEvents[event],
            onceList = onceEvents[event];
        if (onList)
            while(onList.indexOf(listener) !== -1) {
                onList.splice(onList.indexOf(listener),1);
            }
        if (onceList)
            while(onceList.indexOf(listener) !== -1) {
                onceList.splice(onceList.indexOf(listener),1);
            }
    };
    
}
/******************************结束写代码******************************/
var count = 0
var input = read_line()
eval(input)
printsth(count)

	function sortStudents(students) {



	    students.sort((a,b)=>{



	        if (a.class === b.class)



	            if (a.score === b.score)



	                return 0;



	            else return b.score - a.score;



	        else return a.class - b.class;



	    });



	    return JSON.stringify(students);



	}