写一个函数，实现21点算法，它根据参数的值来递增或递减变量？

var count = 0;
function cc(card) {
var cards={2:1,3:1,4:1,5:1,6:1,7:0,8:0,9:0,10:-1,“J”:-1,“Q”:-1,“K”:-1,“A”:-1};
count=count+cards[card];
if(count>0){
return count+" Bet";
}else{
return count+" Hold";
}
}
cc(2); cc(3); cc(7); cc(‘K’); cc(‘A’);