#include<bits/stdc++.h>
using namespace std;
map<int,int> m;//存储学号出现的次数 
int main()
{
    int n,x;
    cin>>n;
    int flag = 0;
    //读入n个学号 
    for(int i = 1;i <= n;i++){
    	cin>>x;
    	if(m.count(x) == 0){
    		m[x] = 1;
		}else{
			flag = 1;
			break;
		}
	}
	cout<<flag;
    return 0;
}

/**************************************************************
	Problem: 1507
	User: admin
	Language: C++
	Result: Accepted
	Time:17 ms
	Memory:2076 kb
****************************************************************/