Submission #693679

#	Time	Username	Problem	Language	Result	Execution time	Memory
693679		zeroesandones	Cryptography (NOI20_crypto)	C++17	11 / 100	33 ms	4584 KiB

Crypto

#include "bits/stdc++.h"
using namespace std;

typedef long long ll;
typedef long double ld;
typedef vector<ll> vi;
typedef pair<ll, ll> pi;

#define FOR(i, j, k) for (ll i = j; i < (ll) k; ++i)
#define FORD(i, j, k) for (ll i = j; i >= (ll) k; --i)
#define nl "\n"
#define sp " "

#define all(x) (x).begin(), (x).end()
#define sc second
#define fr first
#define pb emplace_back

const int mod = 1e9 + 7;

ll add(ll x, ll y) {
    return (x % mod + y % mod) % mod;
}

ll factorial(ll n) {
    ll res = 1;
    while(n) {
        res *= n;
        res %= mod;
        --n;
    }

    return (res % mod);
}

void solve()
{
    ll n;
    cin >> n;

    vi a(n);
    FOR(i, 0, n)
        cin >> a[i];

    ll k = a[0];

    ll ans = 0;
    ans = (((k - 1) * factorial(n - 1)) % mod + 1) % mod;

    cout << ans << nl;
}

signed main()
{
    ios_base::sync_with_stdio(false);
    cin.tie(NULL);

    ll t = 1;
    // cin >> t;
    while (t--)
    {
        solve();
    }
}

• Subtask 1: 0 / 5
• Subtask 2: 0 / 9
• Subtask 3: 0 / 10
• Subtask 4: 11 / 11
• Subtask 5: 0 / 21
• Subtask 6: 0 / 13
• Subtask 7: 0 / 19
• Subtask 8: 0 / 12