Submission #1268604

#	Time	Username	Problem	Language	Result	Execution time	Memory
1268604		nhnguyen14	Olympic Bus (JOI20_ho_t4)	C++20	5 / 100	1095 ms	1668 KiB

ho_t4

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

#define FOR(i,a,b) for(int i = (a) , _b = (b); i <= _b; ++i)
#define MASK(x) ((LL)(1) << (x))
#define BIT(mask , x) (((mask) >> (x)) & (1))
#define sz(x) (int)(x).size()
#define TIME_USED cerr << "\n Time lapsed : " << 1.0 * clock() / CLOCKS_PER_SEC << "s\n";

template<class T1 , class T2>
	bool maximize(T1 &a , T2 b){
		if (a < b) return a = b , true; else return false;
	}
template<class T1 , class T2>
	bool minimize(T1 &a , T2 b){
		if (a > b) return a = b , true; else return false;
	}
template<class T>
	void compress(vector<T>&data){
		sort(data.begin() , data.end());
		data.resize(unique(data.begin() , data.end()) - data.begin());
	}
template<class T1 , class T2>
	T2 Find(const vector<T1>&data , T2 y){
		return upper_bound(data.begin() , data.end() , y) - data.begin();
	}

const int N = (int) 200;
const int M  = (int) 5e4;
const LL inf = (LL)1e18;
	int x[M + 2] , y[M + 2] , c[M + 2] , d[M + 2];
	bool ban[M + 2] = {};
	int n , m;

	vector<int> ke[N + 2];
		void add_canh(int u , int v , int id){
			ke[u].push_back(id);
			return;
		}
		
	LL dist[2][N + 2];
		LL djisktra(int source , int sink){
			for(int i = 1; i <= n; ++i) ke[i].clear();
			for(int i = 1; i <= n; ++i) dist[0][i] = dist[1][i] = inf;
			for(int i =1; i <= m; ++i) {
				if (ban[i]==false) add_canh(x[i] , y[i] , i);
					else add_canh(y[i] , x[i] , i);
			}	
			priority_queue<pair<LL,int> , vector<pair<LL,int>> , greater<pair<LL,int>>> pq;
			dist[0][1] = 0;
			pq.push({dist[0][1] , 1});
			while (pq.size()){
				int u = pq.top().second;
				LL cost = pq.top().first;
				pq.pop();
				if (cost != dist[0][u]) continue;
				for(int id : ke[u]){
					int v = u  ^ x[id] ^ y[id];
					if (minimize(dist[0][v] , cost + c[id])){
						pq.push({dist[0][v] , v});
					}
				}
			}
			dist[1][n] = 0;
			pq.push({dist[1][n] , n});
			while (pq.size()){
				int u = pq.top().second;
				LL cost = pq.top().first;
				pq.pop();
				if (cost != dist[1][u]) continue;
				for(int id : ke[u]){
					int v = u  ^ x[id] ^ y[id];
					if (minimize(dist[1][v] , cost + c[id])){
						pq.push({dist[1][v] , v});
					}
				}
			}
			return dist[0][n] + dist[1][1];
		}
	
int main(){
	ios::sync_with_stdio(false);
	cin.tie(0) ; cout.tie(0) ;
	#define name "main"
		if (fopen(name".inp","r")){
			freopen(name".inp","r",stdin);
			freopen(name".out","w",stdout);
		}
		
		cin >> n >> m;
		for(int i = 1; i <= m; ++i) {
			cin >> x[i] >> y[i] >> c[i] >> d[i];
			ban[i] = false;
		}
		
		LL ans = djisktra(1 , n);
		for(int i = 1; i <= m; ++i){
			ban[i] = true;
			minimize(ans , djisktra(1 , n) + d[i]);
			ban[i] = false;
		}
		if (ans >= inf) ans = -1;
		cout << ans;
		
	return 0;
}

Compilation message (stderr)

ho_t4.cpp: In function 'int main()':
ho_t4.cpp:87:32: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   87 |                         freopen(name".inp","r",stdin);
      |                         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~
ho_t4.cpp:88:32: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   88 |                         freopen(name".out","w",stdout);
      |                         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~

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