Submission #1242421

#	Time	Username	Problem	Language	Result	Execution time	Memory
1242421		bangan	Overtaking (IOI23_overtaking)	C++20	65 / 100	3593 ms	25412 KiB

overtaking

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

#define ll long long
#define chmin(a, b) a = min(a, b)
#define chmax(a, b) a = max(a, b)

#define pb push_back
#define ALL(a) a.begin(), a.end()

int n;
vector<ll> t, w;

int m;
vector<ll> s;

vector<vector<ll>> f;
vector<vector<ll>> pre;
vector<vector<ll>> og;

void prep() {
    f = pre = og = vector(m, vector<ll>(n));
    for (int i=0; i<n; i++) f[0][i] = t[i];

    for (int i=1; i<m; i++) {
        for (int j=0; j<n; j++) f[i][j] = f[i-1][j] + (s[i] - s[i-1]) * w[j];
        
        vector<int> ord(n);
        iota(ALL(ord), 0);
        sort(ALL(ord), [&](int p, int q) {
            return f[i-1][p] < f[i-1][q];
        });

        ll mx=0;
        for (auto l=ord.begin(); l != ord.end();) {
            auto r = l;
            while (r != ord.end() && f[i-1][*l]==f[i-1][*r]) r++;
            
            for (auto it=l; it!=r; it++) chmax(f[i][*it], mx);
            for (auto it=l; it!=r; it++) chmax(mx, f[i][*it]);
            l = r;
        }

        for (int j=0; j<n; j++) og[i][j] = f[i-1][ord[j]];
        pre[i][0] = f[i][ord[0]];
        for (int j=1; j<n; j++) pre[i][j] = max(pre[i][j-1], f[i][ord[j]]);
    }
}

void init(int L, int N, std::vector<long long> T, std::vector<int> W, int X, int M, std::vector<int> S) {
    n = N;
    for (auto it : T) t.pb(it);
    t.pb(0);
    for (auto it : W) w.pb(it);
    w.pb(X);

    m = M;
    for (auto it : S) s.pb(it);

    assert(s[0]==0);
    assert(s[m-1]==L);

    prep();
}

ll arrival_time(ll Y) {
    vector<ll> res(m);
    res[0] = Y;

    for (int i=1; i<m; i++) {
        int lo = -1, hi = n;
        while (1 < hi-lo) {
            int mid = (lo+hi) / 2;
            res[i-1] <= og[i][mid] ? hi = mid : lo = mid;
        }

        res[i] = res[i-1] + w[n] * (s[i] - s[i-1]);
        if (lo != -1) chmax(res[i], pre[i][lo]);
    }   

    return res[m-1];
}

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