Created
July 7, 2014 18:41
-
-
Save walkingtospace/d640ca2b3625357215ab to your computer and use it in GitHub Desktop.
single-number XOR
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
https://oj.leetcode.com/problems/single-number/ | |
Given an array of integers, every element appears twice except for one. Find that single one. | |
Note: | |
Your algorithm should have a linear runtime complexity. Could you implement it without using extra memory? | |
/* | |
솔직히 이건.. 알고리즘적 사고 테스트라기보단, XOR을 이용한 trick에 가깝다. | |
예전에 메모리가 진짜 부족할때 XOR을 이용한 코딩을 종종했다고함.(swap) | |
*/ | |
class Solution { | |
public: | |
int singleNumber(int A[], int n) { | |
int res = 0; | |
for(int i=0; i<n ; i++) { | |
res ^= A[i]; | |
} | |
return res; | |
} | |
}; |
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment