Submission #379930

#	Time	Username	Problem	Language	Result	Execution time	Memory
379930		SavicS	Ferries (NOI13_ferries)	C++14	40 / 40	300 ms	19824 KiB

ferries

#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
#include <bits/stdc++.h>

#define fi first
#define se second
#define pb push_back
#define sz(a) (int)a.size()
#define all(a) a.begin(), a.end()
#define rall(a) a.rbegin(), a.rend()
#define ff(i,a,b) for(int i=a;i<=b;i++)
#define fb(i,b,a) for(int i=b;i>=a;i--)

using namespace std;
using namespace __gnu_pbds;
typedef long long ll;
typedef pair<int,int> pii;
const int maxn = 100005;
const int inf = 1e9 + 5;

template<typename T>
using ordered_set = tree<T, null_type, less<T>, rb_tree_tag, tree_order_statistics_node_update>;

// os.order_of_key(k) the number of elements in the os less than k
// *os.find_by_order(k)  print the k-th smallest number in os(0-based)

int n, m;

vector<int> g[maxn];
vector<ll> cost[maxn];

ll dist[maxn];
void dij(int s){
	ff(i,1,n)dist[i] = inf;
	priority_queue<pii, vector<pii>, greater<pii>> pq;
	pq.push({dist[s] = 0, s});
	while(!pq.empty()){
		pii v = pq.top(); pq.pop();
		if(dist[v.se] < v.fi)continue;
		for(auto u : g[v.se]){
			ll w = cost[u].back(); cost[u].pop_back();
			if(dist[u] > v.fi + w){
				dist[u] = v.fi + w;
				pq.push({dist[u], u});
			}
		}
	}
}

int main()
{
    ios::sync_with_stdio(false);
    cout.tie(nullptr);
    cin.tie(nullptr);
	cin >> n >> m;
	ff(i,1,m){
		int u, v;
		ll w;
		cin >> u >> v >> w;
		g[v].pb(u);
		cost[u].pb(w);
	}
	ff(i,1,n)sort(all(cost[i]));
	dij(n);
	cout << dist[1] << endl;
    return 0;
}
/**

4 5
1 2 2
2 4 2
1 3 10
3 4 7
1 4 7

// probati bojenje sahovski ili slicno

**/

• Subtask 1: 7 / 7
• Subtask 2: 10 / 10
• Subtask 3: 11 / 11
• Subtask 4: 12 / 12