17 Good Number
Problem Statement
Write a Recursive Approach to Check if a Given Digit String Represents a Good Number.
A digit string is good if the digits (0-indexed) at even indices are even and the digits at odd indices are prime ((2, 3, 5, or 7).
Examples:
| Sr # | Input | Expected Output | Description |
|---|---|---|---|
| 1 | 02468 | Not Good | Number 6 at index 3 is not a prime number. |
| 2 | 23478 | Good | All digits at even indices are even, and all digits at odd indices are prime. Therefore, the digit string is considered "good". |
| 3 | 224365 | Good | All digits at even indices are even, and all digits at odd indices are prime. Therefore, the digit string is considered "good". |
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