Submission #537368

#	Time	Username	Problem	Language	Result	Execution time	Memory
537368		Gurban	Jakarta Skyscrapers (APIO15_skyscraper)	C++17	57 / 100	396 ms	262144 KiB

skyscraper

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

using ll = long long;

const int maxn=3e4+5;
const int B = 180;
int n,m,st,fn;
int dis[maxn * B];
bool vis[maxn * B];
vector<pair<int,int>>E[maxn * B];

int main(){
	ios::sync_with_stdio(false);
	cin.tie(0);

	cin >> n >> m;
	int sq = sqrt(n)+1;
	for(int i = 0;i < n;i++){
		for(int j = 1;j < sq;j++){
			E[i * sq + j].push_back({i * sq,0});
			if(i - j >= 0) E[i * sq + j].push_back({(i - j) * sq + j,1});
			if(i + j < n) E[i * sq + j].push_back({(i + j) * sq + j,1});
		}
	}
	for(int i = 0;i < m;i++){
		int b,p; cin >> b >> p;
		if(i == 0) st = b;
		if(i == 1) fn = b;
		if(p < sq) E[b * sq].push_back({b * sq + p,0});
		else {
			for(int j = 1;b - j * p >= 0;j++) E[b * sq].push_back({(b - j * p) * sq,j});
			for(int j = 1;b + j * p < n;j++) E[b * sq].push_back({(b + j * p) * sq,j});
		}
	}

	for(int i = 0;i < n * sq;i++) dis[i] = 1e9;
	
	// cout<<st<<' '<<fn<<'\n';

	dis[st * sq] = 0;
	priority_queue<pair<int,int>>q;
	q.push({0,st * sq});
	while(!q.empty()){
		int x = q.top().second;
		q.pop();
		if(vis[x]) continue;
		vis[x] = 1;
		// cout<<x<<'\n';
		for(auto i : E[x]){
			if(dis[i.first] > dis[x] + i.second){
				dis[i.first] = dis[x] + i.second;
				q.push({-dis[i.first],i.first});
			}
		}
	}
	if(dis[fn * sq] == 1e9) cout<<-1;
	else cout<<dis[fn * sq];
}

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