Single Number

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

位操作特性 0^k=k, k^k=0 所以把数组中的所有数xor一遍得出的结果就是仅出现一遍的数字

public int singleNumber(int[] nums) {
   int result = nums[0];
   for (int i = 1; i < nums.length; i++) {
       result^=nums[i];
   }
   return result;
}