136. Single Number

Giới thiệu bài toán

Chi tiết: https://leetcode.com/problems/single-number/

Yêu cầu

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 * 10^4
• 3 * 104 <= nums[i] <= 3 * 10^4
• Each element in the array appears twice except for one element which appears only once.

Giải quyết bài toán

C#

public class Solution {
    public int SingleNumber(int[] nums) {
        int result = 0;
        foreach (var num in nums) {
            result = result ^ num;
        }
        return result;
    }
}

TypeScript

function singleNumber(nums: number[]): number {
    var result = 0;
    nums.forEach(x => result = result ^ x)
    return result;
};

Tham khảo:

• C#
• TypeScript