Submission #499521

#	Time	Username	Problem	Language	Result	Execution time	Memory
499521		Stickfish	Jakarta Skyscrapers (APIO15_skyscraper)	C++17	57 / 100	18 ms	1612 KiB

skyscraper

#include <iostream>
#include <bitset>
#include <deque>
#include <vector>
using namespace std;

const int MAXN = 2001;
bitset<MAXN> used[MAXN];
bitset<MAXN> used_sky;
vector<int> dog[MAXN];

signed main() {
    int n, m;
    cin >> n >> m;
    deque<pair<pair<int, int>, int>> q;
    int togo = 0;
    for (int i = 0; i < m; ++i) {
        int j, p;
        cin >> j >> p;
        dog[j].push_back(p);
        if (i == 0) {
            q.push_back({{j, p}, 0});
            used[j][p] = 1;
        } else if (i == 1) {
            togo = j;
        }
    }
    while (q.size()) {
        auto [pr, d] = q.front();
        auto [j, p] = pr;
        q.pop_front();
        if (j == togo) {
            cout << d << endl;
            return 0;
        }
        if (!used_sky[j]) {
            used_sky[j] = 1;
            for (auto p0 : dog[j]) {
                if (!used[j][p0]) {
                    used[j][p0] = 1;
                    q.push_front({{j, p0}, d});
                }
            }
        }
        if (j >= p && !used[j - p][p]) {
            used[j - p][p] = 1;
            q.push_back({{j - p, p}, d + 1});
        }
        if (j + p < n && !used[j + p][p]) {
            used[j + p][p] = 1;
            q.push_back({{j + p, p}, d + 1});
        }
    }
    cout << -1 << endl;
}

• Subtask 1: 10 / 10
• Subtask 2: 12 / 12
• Subtask 3: 14 / 14
• Subtask 4: 21 / 21
• Subtask 5: 0 / 43