Submission #380385

#	Time	Username	Problem	Language	Result	Execution time	Memory
380385		dannyboy20031204	Jakarta Skyscrapers (APIO15_skyscraper)	C++17	10 / 100	72 ms	110592 KiB

skyscraper

#include<bits/stdc++.h>
#define ll long long
#define fi first
#define se second
using namespace std;
const int N = 30000, inf = 1e9 + 7; //
struct node{
    int a, b, dis;
};
int main(){
    ios::sync_with_stdio(0), cin.tie(0);
    int n, m;
    cin >> n >> m;
    deque<node> q;
    vector<int> pos[n];
    int d[m], x[m];
    for (int i = 0; i < m; i++){
        int x[i];
        cin >> x[i] >> d[i];
        pos[x[i]].push_back(i);
    }
    bitset<900000000> vis{};
    int ans = inf;
    q.push_back({0, x[0], 0});
    vis[x[0]] = true;
    while(!q.empty()){
        node u = q.front();
        q.pop_front();
        //cout << u.a << ' ' << u.b << ' ' << u.dis << '\n';
        if (u.b + d[u.a] < n and !vis[u.a * N + u.b + d[u.a]]){
            q.push_back({u.a, u.b + d[u.a], u.dis + 1});
            vis[u.a * N + u.b + d[u.a]] = true;
        }
        if (u.b - d[u.a] >= 0 and !vis[u.a * N + u.b - d[u.a]]){
            q.push_back({u.a, u.b - d[u.a], u.dis + 1});
            vis[u.a * N + u.b - d[u.a]] = true;
        }
        while (!pos[u.b].empty()){
            int v = pos[u.b].back();
            pos[u.b].pop_back();
            if (!vis[v * N + u.b]){
                q.push_front({v, u.b, u.dis});
                vis[v * N + u.b] = true;
            }
        }
        if (u.a == 1) ans = min(ans, u.dis);
    }
    cout << (ans == inf ? -1 : ans);
}

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