Submission #68805

#	Time	Username	Problem	Language	Result	Execution time	Memory
68805		FedericoS	Jakarta Skyscrapers (APIO15_skyscraper)	C++14	10 / 100	5 ms	1364 KiB

skyscraper

#pragma GCC optimize("Ofast")
#include <iostream>
#include <vector>
#include <queue>
using namespace std;
typedef pair<pair<int,int>,int> pp;

int N,M;
int B[30005],P[30005];
vector<int> V[30005];
priority_queue<pp> Q;

int main(){

	cin>>N>>M;
	for(int i=0;i<M;i++){
		cin>>B[i]>>P[i];
		if(i)
			V[B[i]].push_back(i);
	}

	//indice distanza posizione
	//   |
	//   |
	//   |
	//   V
	//dist pos ind


	Q.push({{0,B[0]},0});

	while(!Q.empty()){

		pp p=Q.top();
		Q.pop();

		//cout<<Q.size()<<" "<<p.second<<" "<<p.first.first<<" "<<p.first.second<<endl;

		if(p.second==1){
			cout<<p.first.first;
			return 0;
		}

		for(int x:V[p.first.second])
			Q.push({{p.first.first,B[x]},x});
		V[p.first.second].clear();

		if(p.first.second==B[p.second]){

			for(int k=1;;k++){
				if(p.first.second-k*P[p.second]<0)
					break;
				if(!V[p.first.second-k*P[p.second]].empty()){
					Q.push({{p.first.first+k,p.first.second-k*P[p.second]},p.second});
					break;
				}
			}

			for(int k=1;;k++){
				if(p.first.second+k*P[p.second]>=N)
					break;
				if(!V[p.first.second+k*P[p.second]].empty()){
					Q.push({{p.first.first+k,p.first.second+k*P[p.second]},p.second});
					break;
				}
			}			

		}

		if(p.first.second<B[p.second]){
			
			for(int k=1;;k++){
				if(p.first.second-k*P[p.second]<0)
					break;
				if(!V[p.first.second-k*P[p.second]].empty()){
					Q.push({{p.first.first+k,p.first.second-k*P[p.second]},p.second});
					break;
				}
			}

		}

		if(p.first.second>B[p.second]){
			
			for(int k=1;;k++){
				if(p.first.second+k*P[p.second]>=N)
					break;
				if(!V[p.first.second+k*P[p.second]].empty()){
					Q.push({{p.first.first+k,p.first.second+k*P[p.second]},p.second});
					break;
				}
			}	

		}

	}

	cout<<-1;

}

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