用switch,哪里错了
var infos=[['小A','女',21,'大一'], ['小B','男',23,'大三'],
['小C','男',24,'大四'], ['小D','女',21,'大一'],
['小E','女',22,'大四'], ['小F','男',21,'大一'],
['小G','女',22,'大二'], ['小H','女',20,'大三'],
['小I','女',20,'大一'], ['小J','男',20,'大三']];
for(var i=0;i<infos.length;i++){
var n = 0;
var arr=[];
switch(infos[i][3]){
case "大一":
arr[n]=infos[i][3];
break;
default:
document.write("<br>");
n++;
}}
for(var j=0;j <arr.length;j++){
switch(arr[j][1]){
case "女":
document.write(arr[j][0]);
break;
default:
document.write("<br>");
}
}