京东前端编程题本地通过，塞码网就是通不过

function intersection(){

	 var A = [1,4,3,3], B = [1,4,5,7], C =[];


	   A = A.concat(B);


	  for(i = 0; i < A.length; i++){


	   if(C.indexOf(A[i]) == -1){


	   C.push(A[i]);


	  }


	  }


	  C.sort();


	  console.log(C.toString().replace(/,/g, " "));


	}

    //第二题
    function fs(n){
    	if(n == 1) return "4";
    	if(n == 2) return "7";
    	var len = Math.pow(2, n);
    	if(n % 2 == 0)
    		return fs(n - Math.ceil(n/2) - 1) + "7";
    	else
    		return fs(n - Math.ceil(n/2) ) + "4";
    }