Submission #998689

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Source Code Expand

#include <cstdio>
#include <cmath>
#include <cstring>
#include <ctime>
#include <climits>
#include <iostream>
#include <algorithm>
#include <set>
#include <map>
#include <queue>
#include <vector>
#include <sstream>
#include <typeinfo>
#include <fstream>

#define DIV 1000000007

using namespace std;

long long N, M, Q;
long long S[100005];
long long T[100005];
long long hen;

//           cost,   ,  dst
vector<pair<long long, long long> >tree[4005];

//           cost,   ,  dst
vector<pair<long long, long long> >ttree[4005];

void solve(long long s, long long t){
	set<long long> done;
	//                     cost  ,   dst
	priority_queue<pair<long long, long long>, vector<pair<long long, long long> >, greater<pair<long long, long long> > > Q;
	long long ans = 0;
	Q.push(make_pair(0, s));
	Q.push(make_pair(0, t));
	while(done.size() < N){
		long long cost, dst;
		cost = Q.top().first;
		dst = Q.top().second;
		Q.pop();
		if(done.count(dst) != 0){
			continue;
		}
		ans += cost;
		done.insert(dst);

		for(int i = 0; i < ttree[dst].size(); i++){
			long long ncost = ttree[dst][i].first;
			long long next = ttree[dst][i].second;
			if(done.count(next) != 0){
				continue;
			}
			Q.push(make_pair(ncost, next));
		}
	}
	cout << ans << endl;
}

void prepare(){
	set<long long> done;
	//                     cost  ,      src	,     dst
	priority_queue<pair<long long, pair<long long, long long> >, vector<pair<long long, pair<long long, long long> > >, greater<pair<long long, pair<long long, long long> > > > Q;
	Q.push(make_pair(0, make_pair(-1, 0)));
	while(done.size() < N){
		long long cost, src, dst;
		cost = Q.top().first;
		src = Q.top().second.first;
		dst = Q.top().second.second;
		Q.pop();
		if(done.count(dst) != 0){
			continue;
		}
		done.insert(dst);
		if(src != -1){
			ttree[src].push_back(make_pair(cost, dst));
			ttree[dst].push_back(make_pair(cost, src));
			hen++;
		}
		for(int i = 0; i < tree[dst].size(); i++){
			long long ncost = tree[dst][i].first;
			long long next = tree[dst][i].second;
			if(done.count(next) != 0){
				continue;
			}
			Q.push(make_pair(ncost, make_pair(dst, next)));
		}
	}
}


int main(){
	cin >> N >> M;
	for(int i = 0; i < M; i++){
		long long a, b, c;
		cin >> a >> b >> c;
		a--;b--;
		tree[a].push_back(make_pair(c, b));
		tree[b].push_back(make_pair(c, a));
	}
	cin >> Q;
	for(int i = 0; i < Q; i++){
		cin >> S[i] >> T[i];
		S[i]--;T[i]--;
	}
	if(Q > 3000){
		return 1;
	}
	
	prepare();
	//cout << "hen = " << hen <<endl;
	if(hen > N){
		return 1;
	}

	for(int i = 0; i < Q; i++){
		solve(S[i], T[i]);
	}
}

Submission Info

Judge Result