The count-and-say sequence is the sequence of integers beginning as
follows:1, 11, 21, 1211, 111221, ...
1
is read off as "one
1"
or 11
.11
is read off
as "two
1s"
or 21
.21
is read off
as "one 2
, then one
1"
or 1211
.
Given an integer n, generate the nth sequence.
Note: The sequence of integers will be represented as a string.
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30 |
public class Solution { /**It is simple problem. * @author Averill Zheng * @version 2014-06-07 * @since JDK 1.7 */ public
String countAndSay( int
n) { String result = "1" ; for ( int
i = 1 ; i < n; ++i){ StringBuffer resultBuffer = new
StringBuffer(); int
length = result.length(); char
currentChar = result.charAt( 0 ); int
count = 0 ; for ( int
j = 0 ; j < length; ++j){ if (currentChar != result.charAt(j)){ resultBuffer.append(count); resultBuffer.append(currentChar - ‘0‘ ); currentChar = result.charAt(j); count = 1 ; } else ++count; } resultBuffer.append(count); resultBuffer.append(currentChar - ‘0‘ ); result = resultBuffer.toString(); } return
result; } } |
leetcode--Count and Say,布布扣,bubuko.com
原文地址:http://www.cnblogs.com/averillzheng/p/3779165.html