Difficulty: Easy
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"```
#### Solution
Language: **Java**
```java
class Solution {
public String countAndSay(int n) {
String tmp = "1";
if (n == 1) {
return tmp;
}
for (int i = 1; i < n; i++) {
tmp = say(tmp);
}
return tmp;
}
private String say(String numStr) {
char tmp = numStr.charAt(0);
int counter = 1;
StringBuilder sb = new StringBuilder();
for (int i = 1; i < numStr.length(); i++) {
if (numStr.charAt(i) == numStr.charAt(i - 1)) {
counter++;
} else {
sb.append(counter).append(tmp);
tmp = numStr.charAt(i);
counter = 1;
}
}
sb.append(counter).append(tmp);
return sb.toString();
}
}
