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#include <bits/stdc++.h>
using namespace std;
typedef long long int ll;
#define endl "\n"
const double PI = 3.14159265358979;
const ll INF = 1e9 + 7;
const ll MOD = 1e9 + 7;
const ll nax = 2505;
const int LOG = 25;
int dijkstra(int start, int end, int capacity, int n, vector<pair<int, int> > adj[], vector<int> &prices) {
vector<vector<int> > dist(n + 1, vector<int> (capacity + 1, INF));
vector<vector<bool> > vis(n + 1, vector<bool> (capacity + 1, false));
priority_queue<pair<int, pair<int, int> > > pq;
dist[start][0] = 0;
pq.push({-dist[start][0], {start, 0}});
while(!pq.empty()) {
auto topElement = pq.top(); pq.pop();
int currCost = -topElement.first;
int currNode = topElement.second.first;
int currFuel = topElement.second.second;
if (vis[currNode][currFuel]) continue;
vis[currNode][currFuel] = true;
// 1. go to a neighbour using a route
for (auto &v: adj[currNode]) {
int neigh = v.first;
int pathLength = v.second;
if (currFuel >= pathLength) {
if (dist[neigh][currFuel - pathLength] > currCost + 0) {
dist[neigh][currFuel - pathLength] = currCost + 0;
pq.push({-dist[neigh][currFuel - pathLength], {neigh, currFuel - pathLength}});
}
}
}
// 2. refill by 1 unit at currNode
if (currFuel < capacity) {
if (dist[currNode][currFuel + 1] > currCost + prices[currNode]) {
dist[currNode][currFuel + 1] = currCost + prices[currNode];
pq.push({-dist[currNode][currFuel + 1], {currNode, currFuel + 1}});
}
}
}
int ans = INF;
for (int i = 0; i <= capacity; i++) {
ans = min(ans, dist[end][i]);
}
return ans;
}
void solve() {
int n, m;
cin >> n >> m;
vector<pair<int, int> > adj[n + 1];
for (int i = 1; i <= m; i++) {
int u, v, d;
cin >> u >> v >> d;
adj[u].push_back({v, d});
adj[v].push_back({u, d});
}
vector<int> prices(n + 1);
for (int i = 1; i <= n; i++) {
cin >> prices[i];
}
int start, end, capacity;
cin >> start >> end >> capacity;
int minCost = dijkstra(start, end, capacity, n, adj, prices);
cout << minCost;
}
signed main() {
ios_base::sync_with_stdio(false);
cin.tie(nullptr);
cout.tie(nullptr);
// int t; cin >> t; while(t--)
solve();
return 0;
}Editor is loading...
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