(4) = RLE of "21" = "1211"

Example 2:

Input: n = 1
Output: "1"
Explanation: This is the base case.

Solution

Method 1 - Recursion

The count-and-say sequence is defined recursively, with countAndSay(1) = "1". Each subsequent term is generated by describing the previous term in terms of the count of consecutive digits. This problem involves generating the nth term in the sequence.

Here is the approach:

Base Case: If n is 1, return "1".
Recursive Generation:
- Start with the initial string "1".
- For each term from 2 to n, generate the next term by reading the current term and applying run-length encoding.
Run-Length Encoding:
- Traverse the string, count consecutive identical digits, and construct the next term by appending the count and the digit.

Code

[{"language":"Java","code":"class Solution {\n    public String countAndSay(int n) {\n        if (n == 1) return \"1\";\n\n        String ans = \"1\";\n        for (int i = 2; i <= n; i++) {\n            ans = nextTerm(ans);\n        }\n\n        return ans;\n    }\n\n

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