Submission #1047913

#	Time	Username	Problem	Language	Result	Execution time	Memory
1047913		qilby	Overtaking (IOI23_overtaking)	C++17	100 / 100	358 ms	59332 KiB

overtaking

#include <bits/stdc++.h>

#include "overtaking.h"

using namespace std;
using ll = long long;

const int N = 1009;

ll n, m, x, w[N], s[N], t[N][N], f[N][N];

void init(int L, int N1, vector < ll > T, vector < int > W, int X, int M, vector < int > S) {
    n = N1, m = M, x = X;

    vector < ll > nw, nt;

    for (int i = 0; i < n; i++) if (W[i] > x) {
        nw.push_back(W[i]);
        nt.push_back(T[i]);
    }

    n = (int)nt.size();
    for (int i = 0; i < n; i++) T[i] = nt[i], w[i] = nw[i];

    for (int i = 0; i < m; i++) s[i] = S[i];

    for (int i = 0; i < n; i++) t[0][i] = T[i];

    for (int i = 1; i < m; i++) {
        ll d = s[i] - s[i - 1];

        vector < vector < ll > > vec;
        for (int j = 0; j < n; j++) vec.push_back({t[i - 1][j], t[i - 1][j] + w[j] * d, j});

        sort(vec.begin(), vec.end());

        ll j = 0, mx = 0;

        while (j < n) {
            int l = j;
            while (l + 1 < n && vec[l][0] == vec[l + 1][0]) l++;

            for (int p = j; p <= l; p++) t[i][vec[p][2]] = max(mx, t[i - 1][vec[p][2]] + w[vec[p][2]] * d);

            while (j <= l) {
                mx = max(mx, vec[j][1]);
                j++;
            }
        }
    }

    for (int i = 0; i < m; i++) sort(t[i], t[i] + n);

    for (int i = 0; i < n; i++) f[m - 1][i] = t[m - 1][i];

    for (int i = m - 2; i >= 0; i--) {
        f[i][0] = t[i][0] + x * (s[m - 1] - s[i]);

        for (int j = 1; j < n; j++) {
            int l = i + 1, r = m - 1;

            while (l < r) {
                int mid = (l + r) >> 1;
                if (t[i][j] + x * (s[mid] - s[i]) <= t[mid][j - 1]) r = mid;
                else l = mid + 1;
            }

            int pt = j - 1;
            while (pt > 0 && t[l][pt - 1] == t[l][pt]) pt--;

            if (t[i][j] + x * (s[l] - s[i]) <= t[l][j - 1]) f[i][j] = f[l][pt];
            else f[i][j] = t[i][j] + x * (s[m - 1] - s[i]);
        }
    }
}

ll arrival_time(ll y) {
    if (y <= t[0][0]) return y + x * s[m - 1];

    int l = 0, r = n - 1;

    while (l < r) {
        int mid = (l + r + 1) >> 1;
        if (t[0][mid] < y) l = mid;
        else r = mid - 1;
    }

    int lg = 1, rg = m - 1;

    while (lg < rg) {
        int mid = (lg + rg) >> 1;
        if (y + x * s[mid] <= t[mid][l]) rg = mid;
        else lg = mid + 1;
    }

    while (l > 0 && t[lg][l - 1] == t[lg][l]) l--;

    if (y + x * s[lg] <= t[lg][l]) return f[lg][l];

    return y + x * s[m - 1];
}

/*int main() {
    //ios_base::sync_with_stdio(0); cin.tie(0);

    ifstream cin("3-21.in");
    ifstream fin("3-21.out");

    int l, q;
    cin >> l >> n >> x >> m >> q;

    vector < ll > T(n);
    vector < int > W(n), S(m);

    for (int i = 0; i < n; i++) cin >> T[i];

    for (int i = 0; i < n; i++) cin >> W[i];

    for (int i = 0; i < m; i++) cin >> S[i];

    init(l, n, T, W, x, m, S);

    for (int it = 1; it <= q; it++) {
        ll y;
        cin >> y;
        ll crr = arrival_time(y, (it == 65 || it == 75));
        ll c;
        fin >> c;
        if (c != crr) cout << "bad! " << it << " " << crr << " " << c << "\n";
    }
}*/

• Subtask 0: 0 / 0
• Subtask 1: 9 / 9
• Subtask 2: 10 / 10
• Subtask 3: 20 / 20
• Subtask 4: 26 / 26
• Subtask 5: 35 / 35