제출 #1242150

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
1242150		M_SH_O	Construction Project 2 (JOI24_ho_t2)	C++20	100 / 100	457 ms	32772 KiB

Main

/*#pragma GCC optimize("O3")
#pragma GCC optimization("Ofast,unroll-loops")
#pragma GCC target("avx2,bmi,bmi2,lzcnt,popcnt")*/
#include <bits/stdc++.h>
/*#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>*/

#define ll long long
#define ll1 long long
#define ull unsigned long long
#define dou long double
#define str string
#define vll vector<ll>
#define vi vector<int>
#define pll pair<ll, ll>
#define vpll vector<pll>
#define vbool vector<bool>
#define vstr vector<str>
#define vvll vector<vll>
#define pb push_back
#define pf push_front
#define endl "\n"
#define fr first
#define se second
// #define sortcmp(a) sort(a.begin(), a.end(), cmp)
#define sort(a) sort(a.begin(), a.end())
#define reverse(a) reverse(a.begin(), a.end())
#define speed ios_base::sync_with_stdio(0);cin.tie(0);cout.tie(0)
#define INF 1000000000000000007
#define ordered_set tree<ll, null_type, less_equal<ll>, rb_tree_tag, tree_order_statistics_node_update>

using namespace std;
//using namespace __gnu_pbds;

mt19937 rng(time(0));
ll randll(ll l, ll r) {
    return uniform_int_distribution<ll>(l, r)(rng);
}

vector<vpll> g;

void dijkstra(ll n, vll& d, vector<vpll>& g1) {
    set<pll> s;
    for (int i = 1; i <= n; i ++) {
        s.insert({d[i], i});
    }

    while (s.size()) {
        pll p = *s.begin();
        s.erase(s.begin());
        for (auto i : g1[p.se]) {
            if (p.fr+i.se < d[i.fr]) {
                s.erase({d[i.fr], i.fr});
                d[i.fr] = p.fr+i.se;
                s.insert({d[i.fr], i.fr});
            }
        }
    }
}

int main(){
    speed;
    srand(time(0));

    ll n, m;
    cin >> n >> m;
    ll a, b, l, k;
    cin >> a >> b >> l >> k;
    g.resize(n+7);

    for (int i =0 ; i < m; i ++) {
        ll a, b, c;
        cin >> a >> b >> c;
        g[a].pb({b, c});
        g[b].pb({a, c});
    }

    vll d(n+7, INF);
    d[a] = 0;
    dijkstra(n, d, g);
    if (d[b] <= k) {
        cout << n*(n-1)/2 << endl;
        return 0;
    }
    vll d_ = d;
    sort(d);
    vll d1(n+7, INF);
    d1[b] = 0;
    dijkstra(n, d1, g);
    ll res = 0;

    for (int i = 1; i <= n; i ++) {
        ll l1 = -1, r1 = n;
        while (r1-l1 > 1) {
            ll x = (l1+r1)/2;
            if (d[x]+l+d1[i] > k) r1 = x;
            else l1 = x;
        }
        res += l1+1;
        if (d1[i]+l+d_[i] <= k) res --;
    }
    cout << res << endl;
}

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