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#include<bits/stdc++.h>
#define N 50005
#define inf 200000000
using namespace std;
ifstream fin("distante.in");
ofstream fout("distante.out");
typedef pair < int, int > Pair; // define our pair for an easier use
class Graph {
private:
int n, m;
vector < Pair > adcost[N]; ///adcost[x] = (y,c) where c = cost for the edge from x->y
public:
Graph() = default;
Graph(int n = 0, int m = 0):n(n), m(m){}
vector<int> dijkstra(int start);
void readUndirectedCost();
};
void Graph::readUndirectedCost() {
for(int i = 1; i <= m; ++i) {
int x, y, cost;
fin >> x >> y >> cost;
adcost[x].push_back(make_pair(y,cost));
adcost[y].push_back(make_pair(x,cost));
}
}
vector<int> Graph::dijkstra(int start) {
///O((e+v)log(v))
///the minimum path from a source to all others
///a priority queue with (cost, vertex) that keep in ascending order the minimum path to a vertex from the start
///at a moment in front of the queue will be a vertex whose path can not be any better
///take that node, itarete its neighbours and try to update path --> if one can be updated read the pair(cost, vertex) in the priority queue
///viz -- if we already decided the minimum path to that node
/// --(bcs at a moment we may have entered multiple times a node in the queue) (first time with a worse price, then with a better one)
priority_queue < Pair, vector < Pair >, greater < Pair > > queue_edges; ///add (for used edges in ascending order of their costs)
///pair(cost, node) where cost = source->node
///for DIJKSTRA
int viz[N] = {0};
vector<int> dist;
dist.reserve(n);
for(int i = 1; i <= n; ++i)
dist[i] = inf;
int source = start; //the start node
queue_edges.push(make_pair(0, source)); ///the cost is 0 to arrive at the source
dist[source] = 0;
while(!queue_edges.empty())//we will add in the queue all the updated paths (cost, node) --> priority queue ordered by their costs
{ //at a moment we will choose the minimum cost existent
int node = queue_edges.top().second;
queue_edges.pop();
if(viz[node] == 1)continue; //skip this node bcs we already had a path to it
else viz[node] = 1; //continue from this node
for(int i = 0; i < adcost[node].size(); ++i)//for all nodes that "node" is connected to
{
int vertex = adcost[node][i].first;
int cost = adcost[node][i].second;
//try to update minimum cost
if(cost + dist[node] < dist[vertex])
{
dist[vertex] = dist[node] + cost;
queue_edges.push(make_pair(dist[vertex], vertex));
}
}
}
return dist;
}
void solveDijkstra() {///THE PATH WITH MINIMUM COST FROM A SPECIFIC NODE
int t;
fin >> t;
for(int k = 1 ;k <= t; ++k)
{
int n, m, start;
fin >> n >> m >> start;
int sol[n];
for(int i = 1; i <= n; ++i)
fin >>sol[i];
Graph g(n, m);
g.readUndirectedCost();
vector<int> dist = g.dijkstra(start);
bool adev = true;
for(int i = 1; i <= n; ++i)
if(dist[i] == inf)
dist[i] = 0;
for(int i = 1; i <= n; ++i)
if(dist[i] != sol[i])
{
adev = false;
break;
}
if(adev == true)
fout <<"DA\n";
else fout <<"NU\n";
}
}
int main() {
solveDijkstra();
return 0;
}