Submission #202312

#	Time	Username	Problem	Language	Result	Execution time	Memory
202312		amoo_safar	Olympic Bus (JOI20_ho_t4)	C++14	5 / 100	1095 ms	2680 KiB

ho_t4

#include <bits/stdc++.h>

#define pb push_back
#define F first
#define S second
#define all(x) x.begin(), x.end()
#define debug(x) cerr << #x << " : " << x << '\n'

using namespace std;

typedef long long ll;
typedef long double ld;
typedef string str;
typedef pair<ll, ll> pll;

const int N = 2e2 + 10;
const int M = 2e5 + 10;
const ll Inf = 1e15;

ll n, m;
ll u[M], v[M], c[M], d[M], ans[M];
ll G[N][N], W[N][N], mk[N], dis[N];

void Build(){
	memset(G, 31, sizeof G);
	memset(mk, 0, sizeof mk);
	memset(dis, 31, sizeof dis);
	memset(W, -1, sizeof W);
	for(int i = 0; i < m; i++){
		G[u[i]][v[i]] = min(G[u[i]][v[i]], c[i]);
		if(G[u[i]][v[i]] == c[i]) W[u[i]][v[i]] = i;
	}
}

ll Solve(int idx){
	swap(u[idx], v[idx]);
	Build();
	dis[1] = 0;
	for(int i = 0; i < n; i++){
		ll mn = Inf, id = -1;
		for(int j = 1; j <= n; j++)
			if(!mk[j] && dis[j] < mn){
				mn = dis[j];
				id = j;
			}
		if(id == -1) break;
		mk[id] = 1;
		for(int j = 1; j <= n; j++)
			if(dis[j] > dis[id] + G[id][j]){
				dis[j] = dis[id] + G[id][j];
			}
	}
	swap(u[idx], v[idx]);
	return dis[n];
}

void Main(){
	for(int i = 0; i < m; i++){
		ans[i] += Solve(i);
	}
	return ;
}

int main(){
	ios::sync_with_stdio(0); cin.tie(0); cout.tie(0);
	cin >> n >> m;
	for(int i = 0; i < m; i++) cin >> u[i] >> v[i] >> c[i] >> d[i];
	ll Ans = Solve(m);
	Main();
	for(int i = 0; i < m; i++){
		if(u[i] == 1 || u[i] == n) u[i] = n + 1 - u[i];
		if(v[i] == 1 || v[i] == n) v[i] = n + 1 - v[i];
	}
	Ans += Solve(m);
	Main();
	for(int i = 0; i < m; i++) Ans = min(Ans, d[i] + ans[i]);
	cout << (Ans < Inf ? Ans : -1) << '\n';
	return 0;
}
/*
4 10
1 2 4 4
1 2 4 4
1 3 2 1
1 3 2 1
4 3 1 2
4 3 1 2
4 1 6 1
4 1 6 1
2 4 2 5
2 4 2 5
*/

• Subtask 1: 5 / 5
• Subtask 2: 0 / 11
• Subtask 3: 0 / 21
• Subtask 4: 0 / 63