CSES - Flight Routes

Time Complexity: $\mathcal{O}(mk\log (mk))$

Maintain a priority queue of the $k$ best distances found for each vertex. We'll iterate through the adjacency list of each vertex at most $k$ times.

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#include <bits/stdc++.h>
using namespace std;
#define ll long long

const int MX = 2e5 + 5;
int n, m, k;
priority_queue<ll> bes[MX];
vector<pair<int, int>> adj[MX];
priority_queue<pair<ll, int>, vector<pair<ll, int>>, greater<pair<ll, int>>> pq;