Submission #1167438

#	Time	Username	Problem	Language	Result	Execution time	Memory
1167438		PlayVoltz	Construction Project 2 (JOI24_ho_t2)	C++20	100 / 100	234 ms	24928 KiB

Main

#include <cstdio>
#include <stdio.h>
#include <stdbool.h>
#include <iostream>
#include <map>
#include <vector>
#include <climits>
#include <stack>
#include <string>
#include <queue>
#include <algorithm>
#include <set>
#include <unordered_set>
#include <unordered_map>
#include <cmath>
#include <cctype>
#include <bitset>
#include <iomanip>
#include <cstring>
#include <numeric>
#include <cassert>
using namespace std;

#define int long long
#define pii pair<int, int>
#define mp make_pair
#define pb push_back
#define fi first
#define se second

int n;
vector<vector<pii> > graph;

vector<int> dijk(int s){
	vector<int> dj(n+1, LLONG_MAX/2);
	vector<bool> visited(n+1, 0);
	priority_queue<pii, vector<pii>, greater<pii> > pq;
	pq.push(mp(0, s));
	dj[s]=0;
	while (pq.size()){
		int node=pq.top().se;
		pq.pop();
		if (visited[node])continue;
		visited[node]=1;
		for (auto num:graph[node])if (!visited[num.fi]&&num.se+dj[node]<dj[num.fi]){
			dj[num.fi]=num.se+dj[node];
			pq.push(mp(dj[num.fi], num.fi));
		}
	}
	return dj;
}

int32_t main(){
	ios_base::sync_with_stdio(0);
	cin.tie(0);
	cout.tie(0);
	int m, s, t, l, k, a, b, c, ans=0;
	cin>>n>>m>>s>>t>>l>>k;
	graph.resize(n+1);
	while (m--){
		cin>>a>>b>>c;
		graph[a].pb(mp(b, c));
		graph[b].pb(mp(a, c));
	}
	vector<int> ds=dijk(s), dt=dijk(t);
	if (ds[t]<=k){
		cout<<n*(n-1)/2;
		return 0;
	}
	vector<pii> vect;
	for (int i=1; i<=n; ++i)vect.pb(mp(dt[i], i));
	sort(vect.begin(), vect.end());
	for (int i=1; i<=n; ++i)ans+=upper_bound(vect.begin(), vect.end(), mp(k-l-ds[i], LLONG_MAX/2))-vect.begin()-(dt[i]<=k-l-ds[i]);
	cout<<ans;
}

• Subtask 1: 8 / 8
• Subtask 2: 16 / 16
• Subtask 3: 29 / 29
• Subtask 4: 47 / 47