#include <iostream>
#include <string>
#include <algorithm>
#include <vector>
#include <stack>
#include <unordered_set>
#include <set>
#include <map>
#include <unordered_map>
#include <iomanip>
#include <climits>
#include <random>
#include <queue>
#include <array>
//#include <fstream>
/*#include <cstdio>
#include <ctime>*/
#include <complex>

using namespace std;

#define f first
#define s second	
const int mxN = 100005;
/*Problem:  */
void solve() {}

int main() {
	ios::sync_with_stdio(0), cin.tie(0);
	//freopen("pairup.in", "r", stdin);
	//freopen("pairup.out", "w", stdout);
	//int t = 1; cin >> t;  while (t--) solve();
	
	int n; cin  >> n;
	vector<bool> b(n + 1);
	bool ans = true;
	for (int x, i = 0; i < n; ++i)
	{
		cin >> x; 
		if (!b[x]) b[x] = true;
		else ans &= false;
	}
	for (int i = 1; ans && i <= n; ++i)
		ans &= b[i];
	cout << (ans ? "Yes\n" : "No\n");
	return 0;
}

#include <iostream>
#include <cmath>
#include <stdio.h>
using namespace std;

int main()
{
    int N;
    cin >> N;

    unsigned long long chebyshev_distance = 0;
    unsigned long long sum = 0;
    unsigned long long sum2 = 0;
    for(int i = 0; i < N; i++) {
        long long x;
        cin >> x;
        if(x < 0) {
            x = -x;
        }
        if(x > chebyshev_distance) {
            chebyshev_distance = x;
        }
        sum += x;
        sum2 += x * x;
    }

    printf("%llu\n%.10f\n%llu\n", sum, sqrt(sum2), chebyshev_distance);

    return 0;
}