Submission #862220

#	Submission time	Handle	Problem	Language	Result	Execution time	Memory
862220	2023-10-17T18:09:17 Z	lrvideckis	Round words (IZhO13_rowords)	C++17	100 / 100	150 ms	64912 KB

rowords

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

#define ssize(x) (int)(x).size()

template <class T> struct BIT {
    vector<T> s;
    BIT() {}
    BIT(int n) : s(n) {}
    BIT(const vector<T>& a) : s(a) {
        for (int i = 0; i < ssize(a); i++) {
            int j = i | (i + 1);
            if (j < ssize(a)) s[j] += s[i];
        }
    }
    inline void update(int i, T d) {
        assert(0 <= i && i < ssize(s));
        for (; i < ssize(s); i |= i + 1) s[i] += d;
    }
    inline T sum(int ri) const {
        assert(0 <= ri && ri <= ssize(s));
        T ret = 0;
        for (; ri > 0; ri &= ri - 1) ret += s[ri - 1];
        return ret;
    }
    inline T sum(int le, int ri) const {
        assert(le <= ri);
        return sum(ri) - sum(le);
    }
};
template <class T> struct lcs_dp {
    T t;
    vector<int> dp;
    lcs_dp(const T& a_t) : t(a_t), dp(ssize(t)) {
        iota(begin(dp), end(dp), 0);
    }
    void push_onto_s(int c) {
        for (int i = 0, v = -1; i < ssize(t); i++)
            if (c == t[i] || dp[i] < v) swap(dp[i], v);
    }
};
template <class T> vector<int> lcs_queries(const T& s, const T& t, const vector<array<int, 3>>& queries) {
    auto n = ssize(s), m = ssize(t), q = ssize(queries);
    vector qs(n, vector(m, vector<array<int, 2>>()));
    for (int i = 0; i < q; i++) {
        auto [s_ri, t_le, t_ri] = queries[i];
        assert(0 <= s_ri && s_ri <= n);
        assert(0 <= t_le && t_le <= t_ri && t_ri <= m);
        if (s_ri == 0 || t_le == m) continue;
        qs[s_ri - 1][t_le].push_back({t_ri, i});
    }
    lcs_dp lcs(t);
    vector<int> res(q);
    for (int i = 0; i < n; i++) {
        lcs.push_onto_s(s[i]);
        vector<int> init(m), dp_inv(m, -1);
        for (int j = 0; j < m; j++) {
            if (lcs.dp[j] == -1) init[j] = 1;
            else dp_inv[lcs.dp[j]] = j;
        }
        BIT<int> bit(init);
        for (int t_le = 0; t_le < m; t_le++) {
            for (auto [t_ri, idx] : qs[i][t_le])
                res[idx] = bit.sum(t_le, t_ri);
            if (dp_inv[t_le] != -1) bit.update(dp_inv[t_le], 1);
        }
    }
    return res;
}

int main() {
    cin.tie(0)->sync_with_stdio(0);
    //freopen("rowords.in", "r", stdin);
    //freopen("rowords.out", "w", stdout);

    string s, t;
    cin >> s >> t;

    int res = 0;

    for(int times = 0; times < 2; times++) {
        vector<array<int, 3>> queries;
        for(int le = 0; le < ssize(t); le++) {
            queries.push_back({ssize(s), le, le + ssize(t)});
        }
        vector<int> all_lcs = lcs_queries(s, t + t, queries);

        res = max(res, *max_element(begin(all_lcs), end(all_lcs)));

        reverse(begin(s), end(s));
    }

    cout << res << '\n';

    return 0;
}

Subtask #1

100.0 / 100.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	0 ms	348 KB	Output is correct
2	Correct	0 ms	348 KB	Output is correct
3	Correct	0 ms	348 KB	Output is correct
4	Correct	1 ms	456 KB	Output is correct
5	Correct	0 ms	344 KB	Output is correct
6	Correct	7 ms	4952 KB	Output is correct
7	Correct	82 ms	47452 KB	Output is correct
8	Correct	116 ms	47448 KB	Output is correct
9	Correct	118 ms	47528 KB	Output is correct
10	Correct	109 ms	47528 KB	Output is correct
11	Correct	117 ms	52192 KB	Output is correct
12	Correct	94 ms	60980 KB	Output is correct
13	Correct	150 ms	60952 KB	Output is correct
14	Correct	127 ms	54488 KB	Output is correct
15	Correct	146 ms	64912 KB	Output is correct
16	Correct	132 ms	52460 KB	Output is correct
17	Correct	83 ms	39248 KB	Output is correct
18	Correct	135 ms	61876 KB	Output is correct
19	Correct	104 ms	47408 KB	Output is correct
20	Correct	137 ms	55624 KB	Output is correct
21	Correct	22 ms	12512 KB	Output is correct
22	Correct	43 ms	21596 KB	Output is correct
23	Correct	61 ms	30044 KB	Output is correct
24	Correct	64 ms	31636 KB	Output is correct
25	Correct	92 ms	43088 KB	Output is correct