Submission #898024

#	Time	Username	Problem	Language	Result	Execution time	Memory
898024		votranngocvy	Jakarta Skyscrapers (APIO15_skyscraper)	C++14	100 / 100	223 ms	113764 KiB

skyscraper

#include <bits/stdc++.h>
using namespace std;

#define int long long
#define pii pair<int,int>
#define piii pair<pii,int>
#define fi first
#define se second
const int N = 3e4 + 5;
bitset<N>vis[N];
int n,m,s,t,a[N],b[N];
vector<int>vec[N];

int bfs() {
    queue<piii>q;
    q.push({{a[1],b[1]},0});
    vis[a[1]][b[1]] = true;
    while (!q.empty()) {
        int u = q.front().fi.fi,steps = q.front().fi.se,d = q.front().se;
        q.pop();
        if (u == a[2]) return d;
        if (u - steps >= 0 && !vis[u - steps][steps]) {
            vis[u - steps][steps] = true;
            q.push({{u - steps,steps},d + 1});
        }
        if (u + steps < n && !vis[u + steps][steps]) {
            vis[u + steps][steps] = true;
            q.push({{u + steps,steps},d + 1});
        }
        for (auto x: vec[u]) {
            if (u - x >= 0 && !vis[u - x][x]) {
                vis[u - x][x] = true;
                q.push({{u - x,x},d + 1});
            }
            if (u + x < n && !vis[u + x][x]) {
                vis[u + x][x] = true;
                q.push({{u + x,x},d + 1});
            }
        }
    }
    return -1;
}

signed main() {
    ios_base::sync_with_stdio(0);
    cin.tie(0); cout.tie(0);
    cin >> n >> m;
    for (int i = 1; i <= m; i++) {
        cin >> a[i] >> b[i];
        vec[a[i]].push_back(b[i]);
    }
    cout << bfs() << "\n";
}

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