本题真的非常简单，就是题目有点晦涩，其实很容易，大概思路就是有个额外的int[] temp来存储read4(char[])每次的结果即可，代码如下:

    1. /**
    2.  * The read4 API is defined in the parent class Reader4.
    3.  *     int read4(char[] buf);
    4.  */
    5. public class Solution extends Reader4 {
    6.   /**
    7.    * @param buf Destination buffer
    8.    * @param n   Number of characters to read
    9.    * @return    The number of actual characters read
    10.    */
    11.   public int read(char[] buf, int n) {
    12.     int total = 0;
    13.     while (true) {
    14.       char[] tmp = new char[4];
    15.       int len = read4(tmp);
    16.       for (int i = 0; i < len; ++i) {
    17.         buf[total] = tmp[i];
    18.         ++total;
    19.       }
    20.       if (total >= n || len < 4) {
    21.         break;
    22.       }
    23.     }
    25.     return Math.min(total, n);
    26.   }
    27. }