Submission #967089

#	Time	Username	Problem	Language	Result	Execution time	Memory
967089		angella	Olympic Bus (JOI20_ho_t4)	C++17	100 / 100	908 ms	21732 KiB

ho_t4

/*
    IN THE NAME OF GOD
*/
#include <bits/stdc++.h>

// #pragma GCC target("avx2,bmi,bmi2,lzcnt,popcnt")
// #pragma GCC optimize("O3")
// #pragma GCC optimize("unroll-loops")

using namespace std;

typedef long long ll;
typedef pair<ll, ll> pll;
typedef pair<int, int> pii;
typedef long double ld;

#define F                                      first
#define S                                      second
#define Mp                                     make_pair
#define pb                                     push_back
#define pf                                     push_front
#define size(x)                                ((ll)x.size())
#define all(x)                                 (x).begin(),(x).end()
#define kill(x)		                           cout << x << '\n', exit(0);
#define fuck(x)                                cout << "(" << #x << " , " << x << ")" << endl
#define endl                                   '\n'

const int N = 3e5+23, lg = 18;
ll Mod = 1e9+7; //998244353;

inline ll MOD(ll a, ll mod=Mod) {a%=mod; (a<0)&&(a+=mod); return a;}
inline ll poww(ll a, ll b, ll mod=Mod) {
    ll ans = 1;
    a=MOD(a, mod);
    while (b) {
        if (b & 1) ans = MOD(ans*a, mod);
        b >>= 1;
        a = MOD(a*a, mod);
    }
    return ans;
}

int n, m, mark[N];
ll ev[N], eu[N], dist[N], c[N], d[N], f[205][205];
vector<int> adj[N];

ll solve(int rt, int e) {
    fill(dist, dist+n+2, 1e18);
    fill(mark, mark+n+2, 0);
    priority_queue<pll, vector<pll>,greater<pll>> pq;
    pq.push({0, rt});
    while(size(pq) > 0) {
        pll v = pq.top(); pq.pop();
        if(mark[v.S]) continue;
        mark[v.S]=1, dist[v.S] = v.F;
        for(int u : adj[v.S]) {
            if(u!=e&&mark[eu[u]]==0) pq.push({v.F+c[u], eu[u]});
        }
        if(v.S == eu[e]) pq.push({v.F+c[e], ev[e]});
    }
    if(rt == 1) return dist[n];
    return dist[1];
}

int main () {
	ios_base::sync_with_stdio(false), cin.tie(0);

	cin>>n>>m;
    for(int i=1; i<=n; i++) {
        for(int j=1; j<=n; j++) if(i!=j) f[i][j] = 1e18;
    }
    for(int i=1; i<=m; i++) {
        cin>>ev[i]>>eu[i]>>c[i]>>d[i];
        adj[ev[i]].pb(i);
        f[ev[i]][eu[i]] = min(c[i], f[ev[i]][eu[i]]);
    }
    for(int i=1; i<=n; i++) {
        for(int j=1; j<=n; j++) {
            for(int k=1; k<=n; k++) {
                f[j][k] = min(f[j][i]+f[i][k], f[j][k]);
            }
        }
    }

    ll ans = f[1][n] + f[n][1];
    for(int i=1; i<=m; i++) {
        if(min(f[1][n],f[1][eu[i]]+f[ev[i]][n]+c[i])+min(f[n][1],f[n][eu[i]]+f[ev[i]][1]+c[i])+d[i] < ans) {
            ans = min(ans, solve(1,i)+solve(n,i)+d[i]);
        }
    }

    cout<<(ans>=1e11 ? -1 : ans)<<endl;

	return 0;
}

• Subtask 1: 5 / 5
• Subtask 2: 11 / 11
• Subtask 3: 21 / 21
• Subtask 4: 63 / 63