The count-and-say sequence is the sequence of integers with the first five terms as following:
1 |
1. 1 |
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:
1 |
Input: 1 |
Example 2:
1 |
Input: 4 |
Hint 1
The following are the terms from n=1 to n=10 of the count-and-say sequence:
- 1
- 11
- 21
- 1211
- 111221
- 312211
- 13112221
- 1113213211
- 31131211131221
- 13211311123113112211
Hint 2
To generate the n th term, just count and say the n-1 th term.
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