Dsa
Two Pointers
Warm-up
Letter Swapper
As part of a simple encryption step, you need to reverse only the alphabetic characters in a string while keeping all digits and special symbols in their original fixed positions.
Input Format:
A single string of characters.
Output Format:
The modified string where only letters are reversed.
Example:
Input: a-b1c
Output: c-b1a
(Explanation: 'a', 'b', and 'c' are reversed to 'c', 'b', 'a', but '-' and '1' stay at indices 1 and 3.)
Key concepts
two_pointersstring_processing
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