[LeetCode fl from scratch] Single Number, leetcodesingle

[LeetCode fl from scratch] Single Number, leetcodesingle

Yes, I am a fan of Wu Sheng 2009. From today on, I copied the "from zero to single row" series and click the LeetCode!

Question:

Given an array of integers, every element appears twice should t for one. Find that single one.

Answer:

In fact, it is to find a different one. This requires a more trick idea:Bitwise operation.

Imagine what is the answer to an exception or operation on any two identical numbers? Is 0. 4 ^ 8 ^ 4 ^ 8 = 0. The middle is separated by N digits.

0 is different from any number. What is the answer? Is this number itself.

Class Solution {public: int singleNumber (int A [], int n) {int sum = A [0]; for (int I = 1; I <n; I ++) sum = sum ^ A [I]; return sum ;}};