The API: int read4(char *buf) reads 4 characters at a time from a file.
The return value is the actual number of characters read. For example, it returns 3 if there is only 3 characters left in the file.
By using the read4 API, implement the function int read(char *buf, int n) that reads n characters from the file.
Note:
The read function will only be called once for each test case.
1 /* The Read4 API is defined in the parent class Reader4. 2 int Read4(char[] buf); */ 3 4 public class Solution : Reader4 { 5 /** 6 * @param buf Destination buffer 7 * @param n Maximum number of characters to read 8 * @return The number of characters read 9 */ 10 public int Read(char[] buf, int n) { 11 int i = 0; 12 bool eof = false; 13 14 while (i < n && !eof) 15 { 16 var temp = new char[4]; 17 int r = Read4(temp); 18 19 if (r < 4) 20 { 21 eof = true; 22 } 23 24 for (int k = 0; k < r; k++) 25 { 26 buf[i++] = temp[k]; 27 28 if (i >= n) break; 29 } 30 } 31 32 return i; 33 } 34 }
