IntegerPalindrome | Topcoder Archive

Problem Statement

A positive integer is called a palindrome if it reads the same forward and backward. Integers containing leading zeros are not valid. For example, 12321 is a palindrome, but 123210 is not. You are given an int K. Return the K-th palindrome, where the 0th palindrome is 1, the 1st palindrome is 2, etc.

Definition

Class:: IntegerPalindrome
Method:: findByIndex
Parameters:: int
Returns:: long
Method signature:: long findByIndex(int K)
(be sure your method is public)

Constraints

K will be between 0 and 1000000000 (109), inclusive

Examples

```
8
```
```
Returns: 9
```
```
9
```
```
Returns: 11
```
```
19
```
```
Returns: 111
```
```
235
```
```
Returns: 13731
```
```
23746
```
```
Returns: 137484731
```

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