Submission #1273354

#	Time	Username	Problem	Language	Result	Execution time	Memory
1273354		SmuggingSpun	Autobus (COCI22_autobus)	C++20	70 / 70	211 ms	2724 KiB

Main

#include<bits/stdc++.h>
#define taskname "B"
using namespace std;
const int lim = 75;
const int INF = 1e9;
template<class T>bool minimize(T& a, T b){
	if(a > b){
		a = b;
		return true;
	}
	return false;
}
struct Data{
	int w, u, t;
	Data(){}
	Data(int w, int u, int t){
		this->w = w;
		this->u = u;
		this->t = t;
	}
	friend bool operator <(const Data a, const Data b){
		return a.w > b.w;
	}
};
int g[lim][lim], dp[lim][lim][lim];
int main(){
	ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0);
	if(fopen(taskname".inp", "r")){
		freopen(taskname".inp", "r", stdin);
	}
	int n, m;
	cin >> n >> m;
	memset(g, 0x3f, sizeof(g));
	for(int _ = 0; _ < m; _++){
		int u, v, w;
		cin >> u >> v >> w;
		minimize(g[u][v], w);
	}
	memset(dp, 0x3f, sizeof(dp));
	for(int i = 1; i <= n; i++){
		priority_queue<Data>pq;
 		pq.push(Data(dp[i][i][0] = 0, i, 0));
 		while(!pq.empty()){
 			Data c = pq.top();
 			pq.pop();
			if(c.t + 1 < lim && c.w == dp[i][c.u][c.t]){
	 			for(int v = 1; v <= n; v++){
					if(g[c.u][v] < INF && minimize(dp[i][v][c.t + 1], c.w + g[c.u][v])){
						pq.push(Data(dp[i][v][c.t + 1], v, c.t + 1));
					}
				}
			}
	  }
	}
	int k, q;
	cin >> k >> q;
	minimize(k, lim - 1);
	for(int _ = 0; _ < q; _++){
		int a, b, ans = INF;
		cin >> a >> b;
		for(int i = 0; i <= k; i++){
			minimize(ans, dp[a][b][i]);
		}
		cout << (ans < INF ? ans : -1) << "\n";
	}
}

Compilation message (stderr)

Main.cpp: In function 'int main()':
Main.cpp:29:24: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   29 |                 freopen(taskname".inp", "r", stdin);
      |                 ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 15 / 15
• Subtask 2: 15 / 15
• Subtask 3: 25 / 25
• Subtask 4: 15 / 15