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Leetcode
Medium
Arrays
Bit Manipulation
Google
Single Number II
Find the one integer that appears exactly once when every other integer appears three times.
Acceptance 0%
Problem Statement
Problem
You are given an integer array nums where every value appears exactly three times, except for one value that appears exactly once.
Return the value that appears only once.
You should aim for a solution that uses constant extra space and runs in linear time.
Notes
- The array may contain negative numbers.
- The unique value is guaranteed to exist.
- All non-unique values appear exactly three times.
Input Format
- One integer array
nums. nums[i]is an integer value.- Every element appears three times except one element that appears once.
Output Format
- Return the integer that appears exactly once.
Constraints
- All values except one occur exactly 3 times.
- The remaining value occurs exactly 1 time.
- Try to use extra space.
Examples
Sample cases returned by the problem API.
Example 1
Input
nums = [2,2,3,2]
Output
3
Explanation
Every number appears three times except 3, which appears once.
Example 2
Input
nums = [0,1,0,1,0,1,99]
Output
99
Explanation
0 and 1 each appear three times, while 99 appears once.
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