Submission #865681

# Submission time Handle Problem Language Result Execution time Memory
865681 2023-10-24T13:59:16 Z azimanov Sequence (BOI14_sequence) C++17
67 / 100
964 ms 82072 KB
#include <bits/stdc++.h>

using namespace std;

typedef long long ll;

template<int mod>
class Modular {
public:
    int val;
    Modular() : val(0) {}
    Modular(int new_val) : val(new_val) {
    }
    friend Modular operator+(const Modular& a, const Modular& b) {
        if (a.val + b.val >= mod) return a.val + b.val - mod;
        else return a.val + b.val;
    }
    friend Modular operator-(const Modular& a, const Modular& b) {
        if (a.val - b.val < 0) return a.val - b.val + mod;
        else return a.val - b.val;
    }
    friend Modular operator*(const Modular& a, const Modular& b) {
        return 1ll * a.val * b.val % mod;
    }
    friend Modular binpow(Modular a, long long n) {
        Modular res = 1;
        for (; n; n >>= 1) {
            if (n & 1) res *= a;
            a *= a;
        }
        return res;
    }
    /* ALTERNATIVE INVERSE FUNCTION USING EXTENDED EUCLIDEAN ALGORITHM
    friend void gcd(int a, int b, Modular& x, Modular& y) {
        if (a == 0) {
            x = Modular(0);
            y = Modular(1);
            return;
        }
        Modular x1, y1;
        gcd(b % a, a, x1, y1);
        x = y1 - (b / a) * x1;
        y = x1;
    }
    friend Modular inv(const Modular& a) {
        Modular x, y;
        gcd(a.val, mod, x, y);
        return x;
    }
    */
    friend Modular inv(const Modular& a) {
        return binpow(a, mod - 2);
    }
    Modular operator/(const Modular& ot) const {
        return *this * inv(ot);
    }
    Modular& operator++() {
        if (val + 1 == mod) val = 0;
        else ++val;
        return *this;
    }
    Modular operator++(int) {
        Modular tmp = *this;
        ++(*this);
        return tmp;
    }
    Modular operator+() const {
        return *this;
    }
    Modular operator-() const {
        return 0 - *this;
    }
    Modular& operator+=(const Modular& ot) {
        return *this = *this + ot;
    }
    Modular& operator-=(const Modular& ot) {
        return *this = *this - ot;
    }
    Modular& operator*=(const Modular& ot) {
        return *this = *this * ot;
    }
    Modular& operator/=(const Modular& ot) {
        return *this = *this / ot;
    }
    bool operator==(const Modular& ot) const {
        return val == ot.val;
    }
    bool operator!=(const Modular& ot) const {
        return val != ot.val;
    }
    bool operator<(const Modular& ot) const {
        return val < ot.val;
    }
    bool operator>(const Modular& ot) const {
        return val > ot.val;
    }
    explicit operator int() const {
        return val;
    }
};

template <int mod>
Modular<mod> any_to_mint(ll a) {
    a %= mod;
    return a < 0 ? a + mod : a;
}

template<int mod>
istream& operator>>(istream& istr, Modular<mod>& x) {
    return istr >> x.val;
}

template<int mod>
ostream& operator<<(ostream& ostr, const Modular<mod>& x) {
    return ostr << x.val;
}

template <int mod = 998244353, int root = 3>
class NTT {
    using Mint = Modular<mod>;
public:
    static vector<int> mult(const vector<int>& a, const vector<int>& b) {
        vector<Mint> amod(a.size());
        vector<Mint> bmod(b.size());
        for (int i = 0; i < a.size(); i++) {
            amod[i] = any_to_mint<mod>(a[i]);
        }
        for (int i = 0; i < b.size(); i++) {
            bmod[i] = any_to_mint<mod>(b[i]);
        }
        vector<Mint> resmod = mult(amod, bmod);
        vector<int> res(resmod.size());
        for (int i = 0; i < res.size(); i++) {
            res[i] = resmod[i].val;
        }
        return res;
    }
    static vector<Mint> mult(const vector<Mint>& a, const vector<Mint>& b) {
        int n = int(a.size()), m = int(b.size());
        if (!n || !m) return {};
        int lg = 0;
        while ((1 << lg) < n + m - 1) lg++;
        int z = 1 << lg;
        auto a2 = a, b2 = b;
        a2.resize(z);
        b2.resize(z);
        nft(false, a2);
        nft(false, b2);
        for (int i = 0; i < z; i++) a2[i] *= b2[i];
        nft(true, a2);
        a2.resize(n + m - 1);
        Mint iz = inv(Mint(z));
        for (int i = 0; i < n + m - 1; i++) a2[i] *= iz;
        return a2;
    }

private:
    static void nft(bool type, vector<Modular<mod>> &a) {
        int n = int(a.size()), s = 0;
        while ((1 << s) < n) s++;
        assert(1 << s == n);
        static vector<Mint> ep, iep;
        while (int(ep.size()) <= s) {
            ep.push_back(binpow(Mint(root), (mod - 1) / (1 << ep.size())));
            iep.push_back(inv(ep.back()));
        }
        vector<Mint> b(n);
        for (int i = 1; i <= s; i++) {
            int w = 1 << (s - i);
            Mint base = type ? iep[i] : ep[i], now = 1;
            for (int y = 0; y < n / 2; y += w) {
                for (int x = 0; x < w; x++) {
                    auto l = a[y << 1 | x];
                    auto r = now * a[y << 1 | x | w];
                    b[y | x] = l + r;
                    b[y | x | n >> 1] = l - r;
                }
                now *= base;
            }
            swap(a, b);
        }
    }
};

const ll inf = 1e18;
const int L = 18;
const int C = 10;
const int N = 1e5 + 10;
const int M = 1e6 + 1e5 + 10;

int cnt_suf[C][M];

ll pw10[L];
int flag[N];
ll dp[(1 << C)][(1 << C)];

int flag_true[N + N];
int rig_true[C][N + N];

int b[N];
int lef[C][N], rig[C][N];
int pref[C][N], suf[C][N];

bool getbit(int mask, int bit) {
    return mask & (1 << bit);
}

ll mask_to_ll(int mask) {
    ll res = 0;
    for (int i = 1; i < C; i++) {
        if (getbit(mask, i)) {
            res = res * 10 + i;
            mask ^= (1 << i);
            break;
        }
    }
    for (int i = 0; i < C; i++) {
        if (getbit(mask, i)) {
            res = res * 10 + i;
        }
    }
    return res;
}

int vec_to_mask(const vector<int>& vec) {
    int mask = 0;
    for (int i : vec) {
        mask |= (1 << i);
    }
    return mask;
}

void init() {
    {
        for (int x = M - 1; x >= 1; x /= 10) {
            cnt_suf[x % 10][M - 1]++;
        }
    }
    for (int i = M - 2; i >= 1; i--) {
        int mask = 0;
        for (int x = i; x >= 1; x /= 10) {
            mask |= (1 << (x % 10));
        }
        for (int c = 0; c < C; c++) {
            if (getbit(mask, c)) {
                cnt_suf[c][i] = cnt_suf[c][i + 1] + 1;
            } else {
                cnt_suf[c][i] = 0;
            }
        }
    }

    pw10[0] = 1;
    for (int i = 1; i < L; i++) {
        pw10[i] = pw10[i - 1] * 10;
    }

    flag[0] = (1 << 0);
    for (int i = 1; i <= N - 1; i++) {
        for (int j = i; j >= 1; j /= 10) {
            flag[i] |= (1 << (j % 10));
        }
        if (i <= 9'999) {
            flag[i] |= (1 << 0); ///////////////////////////////////////////////////////////////////////////////////////
        }
    }

    flag_true[0] = (1 << 0);
    for (int i = 1; i <= 2 * N - 1; i++) {
        for (int j = i; j >= 1; j /= 10) {
            flag_true[i] |= (1 << (j % 10));
        }
    }

    for (int i = 0; i < (1 << C); i++) {
        for (int j = 0; j < (1 << C); j++) {
            dp[i][j] = inf;
        }
    }
    for (int mask = 0; mask < (1 << C); mask++) {
        for (int last = 0; last < C && last != 9; last++) {
            if (mask == 0 && last == 0) {
                continue;
            }
            int pref_mask = mask | (1 << last);
            int suf_mask = mask | (1 << (last + 1));
            if (mask_to_ll(mask) != 0 || last != 0) {
                dp[pref_mask][suf_mask] = min(dp[pref_mask][suf_mask], mask_to_ll(mask == 1 ? 3 : mask) * 10 + last);
            }

            pref_mask = mask | (1 << last) | (1 << 9);
            suf_mask = mask | (1 << (last + 1)) | (1 << 0);
            dp[pref_mask][suf_mask] = min(dp[pref_mask][suf_mask], mask_to_ll(mask == 1 ? 3 : mask) * 100 + last * 10 + 9);
        }
    }
    for (int i = (1 << C) - 1; i >= 0; i--) {
        for (int j = (1 << C) - 1; j >= 0; j--) {
            for (int c = 0; c < C; c++) {
                dp[i][j] = min(dp[i][j], dp[i | (1 << c)][j]);
                dp[i][j] = min(dp[i][j], dp[i][j | (1 << c)]);
            }
        }
    }
}

void calc_lef_rig(int k) {
    const int n = 100'000;
    for (int c = 0; c < C; c++) {
        vector<int> p(n, 0);
        vector<int> q(k, 0);
        for (int i = 0; i < n; i++) {
            p[i] = getbit(flag[i], c);
        }
        for (int i = 1; i <= k; i++) {
            q[k - i] = b[i] == c;
        }
        auto r = NTT<998244353, 3>::mult(p, q);
        for (int i = 0; i < n; i++) {
            lef[c][i] = r[i];
            rig[c][i] = r[i + k - 1];
        }
    }
}

void calc_pref_suf(int k) {
    for (int c = 0; c < C; c++) {
        pref[c][0] = 0;
        suf[c][k + 1] = 0;
    }
    for (int i = 1; i <= k; i++) {
        for (int c = 0; c < C; c++) {
            pref[c][i] = pref[c][i - 1];
        }
        pref[b[i]][i]++;
    }
    for (int i = k; i >= 1; i--) {
        for (int c = 0; c < C; c++) {
            suf[c][i] = suf[c][i + 1];
        }
        suf[b[i]][i]++;
    }
}

void calc_rig_true(int k) {
    const int n = 200'000;
    for (int c = 0; c < C; c++) {
        vector<int> p(n, 0);
        vector<int> q(k, 0);
        for (int i = 0; i < n; i++) {
            p[i] = getbit(flag_true[i], c);
        }
        for (int i = 1; i <= k; i++) {
            q[k - i] = b[i] == c;
        }
        auto r = NTT<998244353, 3>::mult(p, q);
        for (int i = 0; i < n; i++) {
            rig_true[c][i] = r[i + k - 1];
        }
    }
}

ll solve_small(int k) {
    const int n = 100'000;
    for (int i = 1; i < n; i++) {
        bool ok = true;
        for (int c = 0; c < C; c++) {
            ok &= rig_true[c][i] == pref[c][k];
        }
        if (ok) {
            return i;
        }
    }
    return inf;
}

ll solve(int k) {
    calc_lef_rig(k);
    calc_rig_true(k);
    calc_pref_suf(k);

    const int n = 100'000;
    ll ans = inf;

    ans = min(ans, solve_small(k));

    for (int i = 0; i < n; i++) {
        if (i + k - 1 < n) {
            int need = 0;
            for (int c = 0; c < C; c++) {
                if (rig[c][i] != pref[c][k]) {
                    need |= (1 << c);
                }
            }
            if (dp[need][0] != inf) {
                ans = min(ans, dp[need][0] * n + i);
            }
//            if (need == 0) {
//                if (i == 0) {
//                    ans = min(ans, pw10[to_string(i + k - 1).size()]);
//                } else {
//                    ans = min(ans, ll(i));
//                }
//            } else {
//                if (need == 1) {
//                    need = 3;
//                }
//                ll x = mask_to_ll(need);
//                ans = min(ans, x * pw10[to_string(i + k - 1).size()] + i);
//            }
        } else {
            int len_pref = n - i;
            int len_suf = k - len_pref;
            int need_pref = 0, need_suf = 0;
            for (int c = 0; c < C; c++) {
                if (rig[c][i] != pref[c][len_pref]) {
                    need_pref |= (1 << c);
                }
                if (lef[c][len_suf - 1] != suf[c][len_suf]) {
                    need_suf |= (1 << c);
                }
            }
            if (dp[need_pref][need_suf] != inf) {
                ans = min(ans, dp[need_pref][need_suf] * n + i);
            }
        }
    }
    return ans;
}

ll solve_same(int k) {
    for (int i = 1; i <= k - 1; i++) {
        if (b[i] != b[i + 1]) {
            return inf;
        }
    }
    for (int n = 1; n + k - 1 <= M - 1; n++) {
        if (cnt_suf[b[1]][n] >= k) {
            return n;
        }
    }
    return -1;
}

ll slow(int k) {
    for (int n = 1; n <= 1000; n++) {
        bool ok = true;
        for (int i = 1; i <= k; i++) {
            ok &= getbit(flag_true[n + i - 1], b[i]);
        }
        if (ok) {
            return n;
        }
    }
    return -1;
}

void stress() {
    mt19937 rnd;
    while (true) {
        int k = rnd() % 100 + 1;
        for (int i = 1; i <= k; i++) {
            b[i] = rnd() % C;
        }
        ll res = slow(k);
        if (res == -1) {
            continue;
        }
        ll ans = solve(k);
        if (ans == res) {
            cout << "OK" << endl;
        } else {
            cout << "WA\n";
            cout << k << "\n";
            for (int i = 1; i <= k; i++) {
                cout << b[i] << " ";
            }
            cout << "\n\n";
            cout << ans << " " << res << "\n";
            break;
        }
    }
    exit(0);
}

void gen_same(int& k, int trg_k, int trg_b) {
    k = trg_k;
    for (int i = 1; i <= k; i++) {
        b[i] = trg_b;
    }
}

void stress_same() {
    mt19937 rnd;
    while (true) {
        int k = rnd() % 1000 + 90000;
        b[1] = rnd() % C;
        for (int i = 2; i <= k; i++) {
            b[i] = b[i - 1];
        }

        ll ans = solve(k);
        ll res = solve_same(k);

        if (ans == res) {
            cout << "OK" << endl;
        } else {
            cout << "WA\n";
            cout << k << "\n";
            cout << "b[i] = " << b[1] << "\n";
            cout << "\n\n";
            cout << ans << " " << res << "\n";
            break;
        }
    }
    exit(0);
}

int main() {
    ios_base::sync_with_stdio(false);
    cin.tie(nullptr);
#ifdef LOCAL
    freopen("input.txt", "r", stdin);
#endif

    init();

    // stress();
    // stress_same();

    // cout << dp[vec_to_mask({1, 2, 3})][vec_to_mask({9, 0, 1, 4})] << "\n";

    int k;
    cin >> k;
    for (int i = 1; i <= k; i++) {
        cin >> b[i];
    }

    // gen_same(k, 90239, 0);

    cout << solve(k) << "\n";
    // cout << solve_same(k) << "\n";

#ifdef LOCAL
    cout << "\nTime elapsed: " << double(clock()) / CLOCKS_PER_SEC << " s.\n";
#endif
}

Compilation message

sequence.cpp: In instantiation of 'static std::vector<int> NTT<mod, root>::mult(const std::vector<int>&, const std::vector<int>&) [with int mod = 998244353; int root = 3]':
sequence.cpp:317:46:   required from here
sequence.cpp:125:27: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  125 |         for (int i = 0; i < a.size(); i++) {
      |                         ~~^~~~~~~~~~
sequence.cpp:128:27: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  128 |         for (int i = 0; i < b.size(); i++) {
      |                         ~~^~~~~~~~~~
sequence.cpp:133:27: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  133 |         for (int i = 0; i < res.size(); i++) {
      |                         ~~^~~~~~~~~~~~
# Verdict Execution time Memory Grader output
1 Correct 497 ms 77508 KB Output is correct
2 Correct 488 ms 79012 KB Output is correct
3 Correct 491 ms 77476 KB Output is correct
4 Correct 493 ms 77496 KB Output is correct
5 Correct 494 ms 77376 KB Output is correct
6 Correct 496 ms 77476 KB Output is correct
7 Correct 492 ms 77484 KB Output is correct
8 Correct 490 ms 79064 KB Output is correct
9 Correct 490 ms 79312 KB Output is correct
10 Correct 485 ms 79060 KB Output is correct
11 Correct 484 ms 79008 KB Output is correct
12 Correct 505 ms 77512 KB Output is correct
13 Correct 489 ms 77468 KB Output is correct
14 Correct 494 ms 79036 KB Output is correct
15 Correct 493 ms 79060 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 491 ms 77504 KB Output is correct
2 Correct 489 ms 79048 KB Output is correct
3 Correct 495 ms 77724 KB Output is correct
4 Correct 488 ms 77476 KB Output is correct
5 Correct 500 ms 77468 KB Output is correct
6 Correct 488 ms 77384 KB Output is correct
7 Correct 487 ms 79044 KB Output is correct
8 Correct 494 ms 77520 KB Output is correct
9 Correct 486 ms 79064 KB Output is correct
10 Correct 506 ms 79028 KB Output is correct
11 Correct 492 ms 79196 KB Output is correct
12 Correct 486 ms 79072 KB Output is correct
13 Correct 493 ms 79004 KB Output is correct
14 Correct 489 ms 77248 KB Output is correct
15 Correct 494 ms 77324 KB Output is correct
16 Correct 489 ms 79136 KB Output is correct
17 Correct 488 ms 79036 KB Output is correct
18 Correct 497 ms 77520 KB Output is correct
19 Correct 492 ms 78844 KB Output is correct
20 Correct 487 ms 79024 KB Output is correct
21 Correct 490 ms 79292 KB Output is correct
22 Correct 486 ms 78980 KB Output is correct
23 Correct 490 ms 78940 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 490 ms 79248 KB Output is correct
2 Correct 490 ms 79144 KB Output is correct
3 Correct 495 ms 79132 KB Output is correct
4 Correct 494 ms 79248 KB Output is correct
5 Correct 490 ms 79040 KB Output is correct
6 Correct 489 ms 79292 KB Output is correct
7 Correct 942 ms 82072 KB Output is correct
8 Correct 643 ms 80032 KB Output is correct
9 Correct 964 ms 80584 KB Output is correct
10 Correct 954 ms 80352 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 490 ms 77480 KB Output is correct
2 Correct 497 ms 78944 KB Output is correct
3 Correct 491 ms 77500 KB Output is correct
4 Correct 498 ms 77252 KB Output is correct
5 Correct 646 ms 79836 KB Output is correct
6 Correct 500 ms 77800 KB Output is correct
7 Correct 488 ms 77488 KB Output is correct
8 Correct 492 ms 79012 KB Output is correct
9 Correct 496 ms 77416 KB Output is correct
10 Correct 488 ms 78968 KB Output is correct
11 Correct 962 ms 80296 KB Output is correct
12 Correct 957 ms 80308 KB Output is correct
13 Correct 493 ms 78880 KB Output is correct
14 Correct 494 ms 79232 KB Output is correct
15 Correct 496 ms 78992 KB Output is correct
16 Correct 490 ms 79008 KB Output is correct
17 Correct 492 ms 77260 KB Output is correct
18 Correct 494 ms 77752 KB Output is correct
19 Correct 484 ms 79060 KB Output is correct
20 Correct 491 ms 79036 KB Output is correct
21 Correct 496 ms 77468 KB Output is correct
22 Correct 488 ms 78912 KB Output is correct
23 Correct 489 ms 78880 KB Output is correct
24 Correct 497 ms 79200 KB Output is correct
25 Correct 488 ms 78864 KB Output is correct
26 Correct 493 ms 79036 KB Output is correct
27 Correct 491 ms 79032 KB Output is correct
28 Correct 486 ms 79180 KB Output is correct
29 Correct 493 ms 79084 KB Output is correct
30 Correct 487 ms 79144 KB Output is correct
31 Correct 497 ms 78968 KB Output is correct
32 Correct 944 ms 80040 KB Output is correct
33 Correct 658 ms 79868 KB Output is correct
34 Correct 951 ms 80544 KB Output is correct
35 Correct 954 ms 80292 KB Output is correct
36 Incorrect 947 ms 80260 KB Output isn't correct
37 Halted 0 ms 0 KB -