Submission #959578

#	Time	Username	Problem	Language	Result	Execution time	Memory
959578		Blagoj	Jakarta Skyscrapers (APIO15_skyscraper)	C++17	10 / 100	2 ms	2292 KiB

skyscraper

#include <bits/stdc++.h>

using namespace std;

#define endl '\n'
#define ll long long
#define all(x) (x).begin(), (x).end()

const int mxn = 30010;

int n, m;
unordered_map<int, ll> best[mxn];
int spot[mxn], jump[mxn], val[mxn];
int dx[] = {-1, 1};

void solve() {
    priority_queue<pair<ll, pair<int, int>>> pq;
    pq.push({0, {spot[0], jump[0]}});
    best[spot[0]][jump[0]] = 0;
    while (pq.size()) {
        ll dist = -pq.top().first, pos = pq.top().second.first, pwr = pq.top().second.second;
        pq.pop();
        if (dist > best[pos][pwr]) continue;
        if (val[pos] != -1) {
            if (!best[pos].count(jump[val[pos]])) best[pos][jump[val[pos]]] = 1e18; 
            if (dist < best[pos][jump[val[pos]]]) {
                best[pos][jump[val[pos]]] = dist;
                pq.push({-dist, {pos, jump[val[pos]]}});
            }
        }
        for (int d = 0; d < 2; d++) {
            int newPos = pos + pwr * dx[d];
            if (0 <= newPos && newPos < n) {
                if (!best[newPos].count(pwr)) best[newPos][pwr] = 1e18; 
                if (dist + 1 < best[newPos][pwr]) {
                    best[newPos][pwr] = dist + 1;
                    pq.push({-best[newPos][pwr], {newPos, pwr}});
                }
            }
        }
    }
    ll ans = 1e18;
    for (auto x : best[spot[1]]) ans = min(ans, x.second);
    cout << (ans != 1e18 ? ans : -1);
}

int main() {
    ios_base::sync_with_stdio(false);
    cin.tie(NULL);
    memset(val, -1, sizeof(val));
    cin >> n >> m;
    for (int i = 0; i < m; i++) {
        cin >> spot[i] >> jump[i];
        val[spot[i]] = i;
    }
    solve();
}

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