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