38. Count and Say

The count-and-say sequence is the sequence of integers with the first five terms as following:

1.     1
2.     11
3.     21
4.     1211
5.     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 where 1 ≤ n ≤ 30, generate the nth term of the count-and-say sequence.

Note: Each term of the sequence of integers will be represented as a string.

 

Example 1:

Input: 1
Output: "1"

Example 2:

Input: 4
Output: "1211"

 1 class Solution {
 2 public:
 3     string countAndSay(int n) {
 4         string cur="1";
 5         
 6         for(int i=1;i<n;++i)
 7         {
 8             int n=1;
 9             string tmp;
10             for(int i=0;i<cur.size();++i)
11             {
12                 if(i<cur.size()-1&&cur[i]==cur[i+1])
13                 {
14                     ++n;
15                     continue;
16                 }
17                 tmp+=to_string(n)+cur[i];
18                 n=1;
19             }
20             cur=tmp;
21         }
22         return cur;
23     }
24 };

 


上一篇:幸运的飞艇筘756677700滚雪球公式规律必中5678码


下一篇:HR 问“你目前有几个 Offer”,聪明人会怎么说?你呢!