217. 存在重复元素

题目链接

#pragma once
#include 
#include
#include

using namespace std;



class Solution 
{
public:
	bool containsDuplicate(vector& nums)
	{
		unordered_set hashset;
		for (int num : nums)
		{
			if (hashset.count(num) > 0)
			{
				return true;
			}
			hashset.insert(num);
		}
		return false;
	}
};


int main()
{
	int arr[] = { 1,2,3,4};

	vector nums;

	for (int i = 0; i < sizeof(arr) / sizeof(int); i++)
	{
		nums.push_back(arr[i]);
	}


	Solution S;
	bool res = S.containsDuplicate(nums);
	if (res)
	{
		cout << "存在重复值！" << endl;
	}
	else
	{
		cout << "不存在重复值！" << endl;
	}



	system("pause");
	return 0;
}