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Leetcode
Medium
Arrays
Hash Maps
Math
Set Mismatch
Find the one duplicated number and the one missing number in an array that should contain the integers from 1 to n.
Acceptance 100%
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Problem Statement
You are given an array of length containing numbers from $1n$. Exactly one number appears twice, and exactly one number is missing.
Return the duplicated number and the missing number.
Input Format
- An integer array
numsof lengthn. - Each value is intended to be in the range
1..n. - Exactly one value is duplicated and exactly one value is absent.
Output Format
Return an array/list of two integers [duplicate, missing].
Constraints
- The array contains integers in the range
1..n. - Exactly one number occurs twice.
- Exactly one number from
1..ndoes not appear.
Examples
Sample cases returned by the problem API.
Example 1
Input
nums = [1,2,2,4]
Output
[2,3]
Explanation
The number 2 appears twice, and 3 is missing from the range 1..4.
Example 2
Input
nums = [3,1,2,5,3]
Output
[3,4]
Explanation
The number 3 is duplicated, and 4 is missing.
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