#include <bits/stdc++.h>
//#include <ext/pb_ds/assoc_container.hpp> // Общий файл.
//#include <ext/pb_ds/tree_policy.hpp> // Содержит класс tree_order_statistics_node_update

#define ll long long
#define ull unsigned long long
#define ld long double
#define len(v) (int)v.size()
#define all(v) v.begin(), v.end()
#define rall(v) v.rbegin(), v.rend()
#define pii pair<int, int>
#define vi vector<int>
#define vii vector<vector<int>>
#define vpii vector<pair<int, int>>
#define dcout cout << setprecision(7)
#define mkp make_pair
#define in(v) for (auto& i : v) cin >> i;
#define out(v) for (auto& i : v) cout << i << ' ';
//#define int long long
//#define ll ull
const int maxn = 3e5 + 10;
const int C = 20;
const int logn = 20;
const int inf = 1e9;
const ll mod = 1e9 + 7;
//const int M = 1e9;
const ull M2 = 998244353;
const ld eps = 1e-9;
using namespace std;
//using namespace __gnu_pbds;

//typedef tree<int, null_type, less<int>, rb_tree_tag, tree_order_statistics_node_update> ordered_set;


// random
//std::mt19937_64 gen(std::chrono::steady_clock::now().time_since_epoch().count());

int gcd(int a, int b) {
    return b ? gcd(b, a % b) : a;
}

ll binpow(ll a, ll p, ll m) {
    if (p == 0) return 1ll;
    else if (p % 2)
        return (binpow(a, p - 1, m) * a) % m;
    else {
        ll d = binpow(a, p / 2, m);
        return (int)((d * d) % m);
    }
}

ll binsqrt(ll x) {
    ll l = 0;
    ll r = 1000000;
    for (int i = 0; i < 200; ++i) {
        ll m = (l + r) / 2;
        if (m * m < x) l = m;
        else r = m;
    }
    return r;
}

int gcd_ext(int a, int b, int& x, int& y) {
    if (b == 0) {
        x = 1;
        y = 0;
        return a;
    }
    int xx, yy, d;
    d = gcd_ext(b, a % b, xx, yy);
    x = yy;
    y = xx - (a / b) * yy;
    return d;
}

ll phi(ll n) {
    ll res = n;
    for (int i = 2; i * i <= n; ++i) {
        if (n % i == 0) {
            while (n % i == 0)
                n /= i;
            res -= res / i;
        }
    }
    if (n > 1)
        res -= res / n;
    return res;
}

void solve() {
    int n, l = -1; cin >> n;
    vi c(n); in(c);

    for (int i = 0; i < n; ++i) {
        if (c[i] == 0) {
            if (l == -1) {
                l = i;
                continue;
            } else {
                cout << "NO";
                return;
            }
        }
        if (c[i] == 2) {
            if (l == -1) {
                l = i;
                continue;
            } else if (i - l != 2) {
                cout << "NO";
                return;
            }
        }
    }

    vi a;
    for (int i = l; i < n; ++i)
        a.push_back(c[i]);
    for (int i = 0; i < l; ++i)
        a.push_back(c[i]);
    //out(a);
    for (int i = 0; i < n; ++i) {
        int cur = i + 1;
        if (abs(a[i] - cur) != 1) {
            cout << "NO";
            return;
        }
        a[i] += (a[i] > cur ? -1 : 1);
    }
    for (int i = 1; i <= n; ++i) {
        if (i != a[i - 1]) {
            cout << "NO";
            return;
        }
    }
    cout << "YES\n" << l + 1;

}

signed main() {
    ios::sync_with_stdio(false);
    cin.tie(nullptr);
    cout.tie(nullptr);

    int T = 1;
    //cin >> T;
    while (T--) {
        solve();
    }
}