Submission #402544

#	Time	Username	Problem	Language	Result	Execution time	Memory
402544		faresbasbs	Jakarta Skyscrapers (APIO15_skyscraper)	C++14	10 / 100	2 ms	1032 KiB

skyscraper

#include <bits/stdc++.h>
#pragma GCC optimize("Ofast")
using namespace std;
bitset<30001> bs,bs2[30001];
vector<int> v[30001];
int n,m,tag;

int main(){
	ios_base::sync_with_stdio(false);
	cout.tie(NULL);
	cin.tie(NULL);
	cin >> n >> m;
	for(int i = 0 ; i < m ; i += 1){
		int a,b;
		cin >> a >> b;
		if(i == 1){
			tag = a;
		}
		v[a].push_back(b);
	}
	queue<pair<int,int>> q;
	for(auto i : v[0]){
		q.push({0,i});
		bs2[0][i] = 1;
	}
	bs[0] = 1;
	int dist = 0;
	while(q.size()){
		queue<pair<int,int>> q2;
		while(q.size()){
			pair<int,int> a = q.front();
			q.pop();
			// cout << a.first << " " << a.second << " " << dist << endl;
			if(!bs[a.first]){
				bs[a.first] = 1;
				for(auto i : v[a.first]){
					q.push({a.first,i}) , bs2[a.first][i] = 1;
				}
			}
			if(a.first+a.second < n && !bs2[a.first+a.second][a.second]){
				q2.push({a.first+a.second,a.second}) , bs2[a.first+a.second][a.second] = 1;
			}
			if(a.first-a.second >= 0 && !bs2[a.first-a.second][a.second]){
				q2.push({a.first-a.second,a.second}) , bs2[a.first-a.second][a.second] = 1;
			}
		}
		q = q2;
		if(bs[tag]){
			cout << dist << '\n';
			return 0;
		}
		dist += 1;
	}
	cout << -1 << endl;
}

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