[LeetCode169]Majority Element求一个数组中出现次数大于n/2的数

题目：

Given an array of size n, find the majority element. The majority element is the element that appears more than ⌊ n/2 ⌋ times.

You may assume that the array is non-empty and the majority element always exist in the array.

思路：可以利用Dictionary将数组中每个数出现的次数记录下来，输出出现次数大于n/2的数

　　或者 将数组排序后，数组中间的数即为所求

代码：

public class Solution {
    public int MajorityElement(int[] nums) {
        int time = nums.Length / 2;
        /*利用Dictionary
        Dictionary<int,int> dic = new Dictionary<int,int>();
        for(int i = 0;i < nums.Length;i++)
        {
            if(!dic.ContainsKey(nums[i]))
                dic.Add(nums[i],0);
        }
        for(int j = 0;j < nums.Length;j++)
        {
            if(dic.ContainsKey(nums[j]))
            {
                dic[nums[j]]++;
                if(dic[nums[j]] > time)
                    return nums[j];
            }
        }
        return 0;
        */

        //将数组排序，中间的数字即为所求
        Array.Sort(nums);
        return nums[time];
    }
}