JavaScript--面试--算法--字符串-2

 //实现字符串反转
 function reverse(str) {
     var str_array = str.split(‘‘);
     var low = 0, height = str_array.length-1;
     while(low < height) {
         var tmp = str_array[low];
         str_array[low] = str_array[height];
         str_array[height] = tmp;
         low ++;
         height --;
     }
     return str_array.join();
 }
 var str="你好，世界";
 console.log(reverse(str));

function reverse_2(str) {
    if (str.length == 1) return str;
    return  str.charAt(str.length-1) + reverse_2(str.substr(0, str.length-1));
}
var str="你好，世界";
console.log(reverse_2(str));