#include <bits/stdc++.h>
#define rep(i,n) for(int i = 0; i < (n); ++i)
using namespace std;
using ll = long long;
using P = pair<int, int>;

int main() {
	int n;
	cin >> n;
	vector<int> a(n),b(n);
	rep(i, n)cin >> a[i];
	sort(a.begin(), a.end());
	rep(i, n)b[i] = i + 1;
	rep(i, n) {
		if (a[i] != b[i]) {
			cout << "No" << endl;
			return 0;
		}
	}
	cout << "Yes" << endl;
	return 0;
}
#include<bits/stdc++.h>
using namespace std;
const int INF = INT_MAX;
const int MOD = 1e9 + 7;
//const int ULTRA = 1e14;
const int PROMAX = 1e6 + 5;
const int PRO = 1e5 + 5;

#define ll long long
#define int ll
#define all(x) x.begin(), x.end()
#define lla(x) x.rbegin(), x.rend()
#define pb push_back
#define ThinkTwice ios_base::sync_with_stdio(false); cin.tie(NULL);
int    dx[] = {-1,  0,  1,  0, -1, -1,  1,  1};
int    dy[] = { 0,  1,  0, -1, -1,  1,  1, -1};
char  dir[] = {'U','R','D','L'};
inline int powmod(int a, int b, int mod) {int res=1; while(b>0) {if(b&1) res=(res*a)%mod; a=(a*a)%mod; b>>=1; } return res;}
inline int power(int a, int b) {int res=1; while(b>0) {if(b&1) res*=a; a*=a; b>>=1;} return res; }
//__________________________________________________________________


void solve() {
    char a, b, c; cin>>a>>b>>c;
    if(a == b && b == c) cout<<"Won\n";
    else cout<<"Lost\n";
}

signed main() {
	ThinkTwice
	int t;

	t = 1;
//	cin>>t;

	for(int i = 1; i<=t; i++) {
//		cout<<"Case "<<i<<": ";
		solve();
	}
}

//__________________________________________________________________
/*
Sample Input:


Sample Output:


*/
