Submission #865680

# Submission time Handle Problem Language Result Execution time Memory
865680 2023-10-24T13:55:52 Z azimanov Sequence (BOI14_sequence) C++17
67 / 100
969 ms 97064 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 = 2e5 + 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];
int rig_true[C][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));
        }
        flag_true[i] = flag[i];
        if (i <= 9'999) {
            flag[i] |= (1 << 0); ///////////////////////////////////////////////////////////////////////////////////////
        }
    }

    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:311:46:   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 494 ms 93856 KB Output is correct
2 Correct 491 ms 95424 KB Output is correct
3 Correct 490 ms 93716 KB Output is correct
4 Correct 490 ms 93892 KB Output is correct
5 Correct 495 ms 93844 KB Output is correct
6 Correct 506 ms 93792 KB Output is correct
7 Correct 497 ms 93996 KB Output is correct
8 Correct 491 ms 95456 KB Output is correct
9 Correct 487 ms 95472 KB Output is correct
10 Correct 490 ms 95440 KB Output is correct
11 Correct 488 ms 95388 KB Output is correct
12 Correct 493 ms 93772 KB Output is correct
13 Correct 494 ms 93912 KB Output is correct
14 Correct 489 ms 95292 KB Output is correct
15 Correct 493 ms 95708 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 497 ms 93864 KB Output is correct
2 Correct 488 ms 95404 KB Output is correct
3 Correct 496 ms 94084 KB Output is correct
4 Correct 492 ms 93908 KB Output is correct
5 Correct 493 ms 93820 KB Output is correct
6 Correct 496 ms 94116 KB Output is correct
7 Correct 492 ms 95456 KB Output is correct
8 Correct 491 ms 93912 KB Output is correct
9 Correct 492 ms 95472 KB Output is correct
10 Correct 494 ms 95416 KB Output is correct
11 Correct 492 ms 95464 KB Output is correct
12 Correct 494 ms 95388 KB Output is correct
13 Correct 490 ms 95388 KB Output is correct
14 Correct 495 ms 93980 KB Output is correct
15 Correct 491 ms 93728 KB Output is correct
16 Correct 490 ms 95356 KB Output is correct
17 Correct 497 ms 95420 KB Output is correct
18 Correct 495 ms 93912 KB Output is correct
19 Correct 495 ms 95384 KB Output is correct
20 Correct 493 ms 95684 KB Output is correct
21 Correct 495 ms 95312 KB Output is correct
22 Correct 497 ms 95708 KB Output is correct
23 Correct 490 ms 95424 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 489 ms 95428 KB Output is correct
2 Correct 505 ms 95756 KB Output is correct
3 Correct 492 ms 95608 KB Output is correct
4 Correct 494 ms 95608 KB Output is correct
5 Correct 492 ms 95736 KB Output is correct
6 Correct 491 ms 95452 KB Output is correct
7 Correct 951 ms 96464 KB Output is correct
8 Correct 648 ms 96252 KB Output is correct
9 Correct 953 ms 97020 KB Output is correct
10 Correct 952 ms 97052 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 496 ms 93780 KB Output is correct
2 Correct 491 ms 95388 KB Output is correct
3 Correct 492 ms 94180 KB Output is correct
4 Correct 499 ms 93852 KB Output is correct
5 Correct 641 ms 96328 KB Output is correct
6 Correct 491 ms 93932 KB Output is correct
7 Correct 496 ms 93856 KB Output is correct
8 Correct 488 ms 95612 KB Output is correct
9 Correct 496 ms 93896 KB Output is correct
10 Correct 497 ms 95584 KB Output is correct
11 Correct 953 ms 97064 KB Output is correct
12 Correct 969 ms 96888 KB Output is correct
13 Correct 490 ms 95564 KB Output is correct
14 Correct 491 ms 95424 KB Output is correct
15 Correct 495 ms 96020 KB Output is correct
16 Correct 489 ms 95388 KB Output is correct
17 Correct 489 ms 93924 KB Output is correct
18 Correct 497 ms 93748 KB Output is correct
19 Correct 493 ms 95392 KB Output is correct
20 Correct 492 ms 95452 KB Output is correct
21 Correct 497 ms 93824 KB Output is correct
22 Correct 499 ms 95424 KB Output is correct
23 Correct 488 ms 95380 KB Output is correct
24 Correct 499 ms 95652 KB Output is correct
25 Correct 495 ms 95420 KB Output is correct
26 Correct 496 ms 95336 KB Output is correct
27 Correct 491 ms 95796 KB Output is correct
28 Correct 491 ms 95468 KB Output is correct
29 Correct 495 ms 95608 KB Output is correct
30 Correct 491 ms 95460 KB Output is correct
31 Correct 490 ms 95512 KB Output is correct
32 Correct 950 ms 96400 KB Output is correct
33 Correct 648 ms 96340 KB Output is correct
34 Correct 955 ms 97040 KB Output is correct
35 Correct 962 ms 96988 KB Output is correct
36 Incorrect 944 ms 96840 KB Output isn't correct
37 Halted 0 ms 0 KB -