Find The Difference · Interview Problem

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Leetcode

Easy

Arrays

Strings

Hash Maps

Bit Manipulation

Find The Difference

Find the one extra character that appears in a shuffled version of a string.

Acceptance 0%

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Problem Statement

Given two strings $s$ and $t$ , where $t$ is formed by shuffling the characters of $s$ and adding exactly one extra character at an arbitrary position, identify the extra character.

Return that character as a single-letter string.

Input Format

Two strings $s$ and $t$
$t$ contains all characters of $s$ plus one additional character
Character order in both strings may be arbitrary

Output Format

Return the extra character that appears in $t$ but not in $s$

Constraints

$0 \le |s| \le 10^4$
$|t| = |s| + 1$
Strings contain lowercase English letters in the common LeetCode formulation

Examples

Sample cases returned by the problem API.

Example 1

Input

s = "abcd", t = "abcde"

Output

"e"

Explanation

The string t contains every character from s plus one extra character, e.

Example 2

Input

s = "ae", t = "aea"

Output

"a"

Explanation

The extra character in t is a.

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