#define _CRT_SECURE_NO_WARNINGS
#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef vector<int> vi;
typedef vector<vi> vvi;
typedef pair<int,int> pii;
#define all(c) (c).begin(), (c).end()
#define loop(i,a,b) for(ll i=a; i<ll(b); i++)
#define rep(i,b) loop(i,0,b)
#define each(e,c) for(auto&e:c)
#define pb push_back
#define eb emplace_back
#define mp make_pair
#define mt make_tuple
#define lb lower_bound
#define ub upper_bound
#ifdef DEBUG
#define dump(...) (cerr<<#__VA_ARGS__<<" = "<<(DUMP(),__VA_ARGS__).str()<<" ["<<__LINE__<<"]"<<endl)
struct DUMP:ostringstream{template<class T>DUMP &operator,(const T&t){if(this->tellp())*this<<", ";*this<<t;return *this;}};
#else
#define dump(...)
#endif
template<class T> ostream& operator<<(ostream& os, vector<T> const& v){
    rep(i,v.size()) os << v[i] << (i+1==v.size()?"":" ");
    return os;
}

int n;
int a[60];
bool used[60];
int x[60];

int main(){
    while(cin >> n){
        memset(x,0,sizeof x);
        rep(i,n){
            cin >> a[i];
            a[i]--;
            used[i] = false;
        }
        rep(i,n){
            if(used[i]) continue;
            int j = a[i];
            int c = 1;
            while(j!=i){
                used[j] = true;
                j = a[j];
                c++;
            }
            x[c]++;
        }
        bool ok = true;
        rep(i,50){
            if(i%2==0 && x[i]%2!=0) ok = false;
        }
        puts(ok ? "Yes" : "No");
    }
}