// 实现函数输入n个数组,返回交集,如输入[1,2,3,4,5] [2,3,5] [1,3,5]返回[3,5]
        function fn(...rest){
            // console.log("[...rest]",[...rest]);//[...rest] (4) [Array(5), Array(3), Array(3), Array(2)]
            let arr=[].concat(...rest);
            // console.log("arr",arr);
            let x=[];
            for(var i=0;i<arr.length-1;i++){
                let count = 0;
                for(var j=1;j<arr.length;j++){
                        if(arr[i]== arr[j]){
                            count++;
                        };
                        // console.log("arr[i],arr[j]",arr[i],arr[j],"count",count);
                        if(count==[...rest].length && x.indexOf(arr[i])<0){
                            x.push(arr[i]);
                            // console.log("x",x);
                            break;//结束循环
                        };
                };
            };
            return x;
        };
        fn([1,2,3,4,5],[2,3,5],[1,3,5],[3,5,8]);