Submission #998087

#	Time	Username	Problem	Language	Result	Execution time	Memory
998087		Malix	Construction Project 2 (JOI24_ho_t2)	C++14	45 / 100	2071 ms	27808 KiB

Main

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

typedef long long ll;
typedef vector<int> vi;
typedef vector<vi> vii;
typedef pair<int,int> pi;
typedef vector<pi> pii;
typedef tuple<int,int,int> tii;

#define REP(i,a,b) for(int i=a;i<b;i++)
#define F first
#define S second
#define PB push_back
#define MP make_pair
#define LSOne(s) ((s)&(-s))

ll INF=1e18+10;
int inf=1e9+10;
ll M=1e9+7;

vector<vector<pair<int,ll>>> a;

void djikistra(vector<ll> &c,int s){
    priority_queue<pi,vector<pi>,greater<pi>> pq;
    c[s]=0;
    pq.push({0,s});
    while(!pq.empty()){
        ll x=pq.top().F;
        int y=pq.top().S;
        pq.pop();
        if(c[y]<x)continue;
        for(auto u:a[y]){
            if(c[u.F]<c[y]+u.S)continue;
            c[u.F]=c[y]+u.S;
            pq.push({c[u.F],u.F});
        }
    }

}

int main() {   
//ios::sync_with_stdio(0);
//cin.tie(0);
//freopen("test_input.txt", "r", stdin);
//freopen("test_output.txt", "w", stdout);
    int n,m;cin>>n>>m;
    int s,t;ll l,k;cin>>s>>t>>l>>k;
    s--;t--;
    a.resize(n);
    vector<ll> b(n,INF),c(n,INF);
    REP(i,0,m){
        int x,y,z;cin>>x>>y>>z;
        x--;y--;
        a[x].PB({y,z});
        a[y].PB({x,z});
    }
    djikistra(b,s);
    djikistra(c,t);
    if(b[t]<=k){
        cout<<((ll)n*(n-1))/2;
        return 0;
    };
    multiset<ll> st;
    REP(i,0,n)st.insert(c[i]);
    ll ans=0;
    REP(i,0,n){
        int p=distance(st.begin(),st.upper_bound(k-l-b[i]));
        ans+=(ll)p;//cout<<p<<" ";
    }
    cout<<ans;
}

• Subtask 1: 0 / 8
• Subtask 2: 16 / 16
• Subtask 3: 29 / 29
• Subtask 4: 0 / 47