Submission #787780

#	Time	Username	Problem	Language	Result	Execution time	Memory
787780		drdilyor	Robots (IOI13_robots)	C++17	76 / 100	3068 ms	37580 KiB

robots

#include "robots.h"
#include <algorithm>
#include <cstring>
#include <functional>
#include <iostream>
#include <cassert>
#include <numeric>
#include <set>
using namespace std;

int putaway(int wrobot, int srobot, int n, int rw[], int rs[], int w[], int s[]) {

    sort(rw, rw + wrobot);
    sort(rs, rs + srobot);

    auto comp_w = [&](int i, int j)->bool{ return w[i] < w[j]; };
    auto comp_s = [&](int i, int j)->bool{ return s[i] < s[j]; };

    int* byw = new int[n];
    int* bys = new int[n];
    iota(byw, byw + n, 0);
    iota(bys, bys + n, 0);
    sort(byw, byw + n, comp_w);
    sort(bys, bys + n, comp_s);

    int* done = new int[n];

    auto check = [&](int time)->bool {
        memset(done, 0, sizeof(*done)*n);

        {
            int toy = 0;
            set<pair<int,int>> st;

            for (int rob = 0; rob < wrobot; rob++) {
                while (toy < n && w[byw[toy]] < rw[rob]) {
                    st.insert({-s[byw[toy]], byw[toy]});
                    toy++;
                }
                for (int rem = 0; rem < time && st.size(); rem++) {
                    done[st.begin()->second] = 1;
                    st.erase(st.begin());
                }
            }
        }

        {
            int toy = 0;
            set<pair<int,int>> st;

            for (int rob = 0; rob < srobot; rob++) {
                while (toy < n && s[bys[toy]] < rs[rob]) {
                    if (!done[bys[toy]])
                        st.insert({-w[bys[toy]], bys[toy]});
                    toy++;
                }
                for (int rem = 0; rem < time && st.size(); rem++) {
                    done[st.begin()->second] = 1;
                    st.erase(st.begin());
                }
            }
        }
        int all_done = accumulate(done, done + n, 1, bit_and<>());
        return all_done;
    };

    int l = -1, r = n +1;
    while (l < r - 1) {
        int mid = (l + r) / 2;
        if (check(mid)) r = mid;
        else l = mid;
    }
    return r == n+1 ? -1 : r;
}

• Subtask 1: 14 / 14
• Subtask 2: 0 / 14
• Subtask 3: 25 / 25
• Subtask 4: 37 / 37
• Subtask 5: 0 / 10