Submission #20693

#	Time	Username	Problem	Language	Result	Execution time	Memory
20693		Namnamseo	Crocodile's Underground City (IOI11_crocodile)	C++14	100 / 100	846 ms	156068 KiB

crocodile

#include <vector>
#include <algorithm>
#include <queue>
#define pb push_back
using namespace std;

typedef pair<int,int> pp;

vector<pp> edge[100010];
typedef long long ll;

ll dijk[100010];
ll scnd[100010];
typedef pair<ll,int> pd;

priority_queue<pd> pq;

int travel_plan(int N, int M, int R[][2], int L[], int K, int P[])
{
	for(int i=0; i<N; ++i){
		dijk[i]=(1LL<<62);
		scnd[i]=(1LL<<62);
	}
	for(int i=0; i<K; ++i){
		int a=P[i];
		dijk[a]=0;
		scnd[a]=0;
		pq.push({scnd[a],a});
	}
	for(int i=0; i<N; ++i) edge[i].clear();
	for(int i=0; i<M; ++i){
		int a=R[i][0], b=R[i][1];
		if(dijk[b]!=0) edge[a].pb({b, L[i]});
		if(dijk[a]!=0) edge[b].pb({a, L[i]});
	}
	for(;pq.size();){
		auto t=pq.top(); pq.pop();
		int x=t.second;
		if(scnd[x] != -t.first) continue;
		//printf("Vis %d; second max %lld\n", x, scnd[x]);
		for(pp yy:edge[x]){
			int y=yy.first; int d=yy.second;
			if(dijk[y]>scnd[x]+d){
				//printf("Check to %d\n", y);
				if(dijk[y]<scnd[y]){
					//puts("Pull secondmin");
					scnd[y] = dijk[y];
					pq.push({-scnd[y],y});
				}
				dijk[y] = scnd[x]+d;
			} else if(scnd[y] > scnd[x]+d){
				scnd[y]=scnd[x]+d;
				pq.push({-scnd[y],y});
			}
		}
	}
	return scnd[0];
}

• Subtask 1: 46 / 46
• Subtask 2: 43 / 43
• Subtask 3: 11 / 11