Given a string, find the repeated character present first in the string.
Examples:
Input : geeksforgeeks Output : g (mind that it will be g, not e.) Input : abcdabcd Output : a Input : abcd Output : 1 No character repeats
Asked in: Goldman Sachs internship
We have discussed different approaches in Find repeated character present first in a string.
How to solve this problem using one traversal of input string?
Method 1 (Traversing from Left to Right) We traverse the string from left to right. We keep track of the leftmost index of every character. If a character repeats, we compare its leftmsot index with current result and update the result if result is greater

First Repeating character is g
Time Complexity : O(n). It does only one traversal of input string.
Auxiliary Space : O(1)
Method 2 (Traversing Right to Left) We traverse the string from right to left. We keep track of the visited characters. If a character repeats, we update the result.

First Repeating character is g
Time Complexity : O(n). It does only one traversal of input string.
Auxiliary Space : O(1)
The method 2 is better than method 1 as it does fewer comparisons.
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