169_Majority Element

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.

 

用dictionary来存储<数字，该数字出现次数>  当出现次数达到要求是，返回该数字即可。

 

public class Solution {
    public int MajorityElement(int[] nums) {
        Dictionary<int, int> dic = new Dictionary<int, int>();
        for(int i = 0; i < nums.Count(); i++)
        {
            if(!dic.ContainsKey(nums[i]))
            {
                dic.Add(nums[i], 1);
                
            }
            else
            {
                dic[nums[i]]++;
            }
            if(dic[nums[i]] > nums.Count() / 2)
            {
                return nums[i];
            }
        }
        
        return 0;
    }
}