Submission #1265354

#	Time	Username	Problem	Language	Result	Execution time	Memory
1265354		canhnam357	Jakarta Skyscrapers (APIO15_skyscraper)	C++20	0 / 100	1 ms	328 KiB

skyscraper

#include <bits/stdc++.h>
using namespace std;
int main()
{
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    int n, m;
    cin >> n >> m;
    vector<vector<int>> p(n);
    int f, s;
    for (int i = 0; i < m; i++) {
        int b, c;
        cin >> b >> c;
        if (i == 0 && b - c < 0 && b + c >= n) {
            cout << -1;
            return 0;
        }
        if (i == 0) f = b, s = c;
        if (c < n) p[b].push_back(c);
    }
    vector<vector<int>> d(n, vector<int>(n, INT_MAX));
    d[f][s] = 0;
    deque<pair<int, int>> dq;
    dq.emplace_front(f, s);
    while (!dq.empty()) {
        auto [b, c] = dq.front();
        dq.pop_front();
        for (int i : p[b]) {
            if (d[b][c] < d[b][i]) {
                d[b][i] = d[b][c];
                dq.emplace_front(b, i);
            }
        }
        if (b - c >= 0 && d[b - c][c] > d[b][c] + 1) {
            d[b - c][c] = d[b][c] + 1;
            dq.emplace_back(b - c, c);
        }
        if (b + c < n && d[b + c][c] > d[b][c] + 1) {
            d[b + c][c] = d[b][c] + 1;
            dq.emplace_back(b + c, c);
        }
    }
    int ans = *min_element(d[1].begin(), d[1].end());
    if (ans == INT_MAX) ans = -1;
    cout << ans;
    return 0;
}

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