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136. Single Number
Solved
Easy
Topics
Companies
Hint

Given a non-empty array of integers nums, every element appears twice except for one. Find that single one.

You must implement a solution with a linear runtime complexity and use only constant extra space.

 

Example 1:

Input: nums = [2,2,1]
Output: 1


Example 2:

Input: nums = [4,1,2,1,2]
Output: 4


Example 3:

Input: nums = [1]
Output: 1


 

Constraints:

1 <= nums.length <= 3 * 104
-3 * 104 <= nums[i] <= 3 * 104
Each element in the array appears twice except for one element which appears only once.
Seen this question in a real interview before?
1/5
Yes
No
Accepted
3.2M
Submissions
4.3M
Acceptance Rate
74.4%
Topics
Array
Bit Manipulation
Companies
0 - 3 months
Google
10
Amazon
5
Bloomberg
3
Meta
2
0 - 6 months
Microsoft
4
Airbnb
2
Palantir Technologies
2
6 months ago
Adobe
20
Apple
17
Yahoo
11
Yandex
8
Uber
5
Zoho
4
tcs
3
Nvidia
2
Hint 1
Think about the XOR (^) operator's property.
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Copyright ©️ 2024 LeetCode All rights reserved
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Java
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class Solution {
    public int singleNumber(int[] nums) {
        
    }
}
Saved
Ln 5, Col 2
Accepted
Runtime: 0 ms
Case 1
Case 2
Case 3
Input
nums =
[2,2,1]
Output
1
Expected
1
Contribute a testcase
Input
1
2
3
[2,2,1]
[4,1,2,1,2]
[1]
Output
1
2
3
1
4
1
Expected
1
2
3
1
4
1

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