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#include <fstream>
#include <iostream>
#include <vector>
#include <queue>
using namespace std;
ifstream fin("distante.in");
ofstream fout("distante.out");
vector<pair<int, int> > g[50010];
int n, m, s, t;
int distante[50010];
void citireGraf() {
fin >> n >> m >> s;
for(int i = 1; i <= n; i++)
g[i].clear();
for(int i = 1; i <= n; i++)
fin >> distante[i];
for(int i = 1; i <= m; i++) {
int a, b, c;
fin >> a >> b >> c;
g[a].push_back({b, c});
g[b].push_back({a, c});
}
}
///dijkstra cu heap - 50p
/*void solve() {
int d[50010];
for(int i = 1; i <= n; i++)
d[i] = -1;
priority_queue<pair<int, int> > q;
q.push({0, s});
bool ok = true;
while(!q.empty()) {
int nod = q.top().second;
int cost = q.top().first;
q.pop();
if(d[nod] != -1) continue;
d[nod] = -cost;
if(d[nod] != distante[nod]) {
ok = false;
break;
}
for(int i = 0; i < g[nod].size(); i++)
q.push({cost - g[nod][i].second, g[nod][i].first});
}
if(ok) fout << "DA\n";
else fout << "NU\n";
}*/
///solutia optima e O(n+m) pt ca nu trebuie sa calculam distantele, ci doar sa verificam daca sunt corecte
void solve() {
bool ok = true;
if(distante[s]) {
fout << "NU\n";
return;
}
for(int i = 1; i <= n; i++) {
if(i == s) continue;
bool egal = false;
for(int j = 0; j < g[i].size(); j++) {
int vecin = g[i][j].first;
int c = g[i][j].second;
if(distante[i] > distante[vecin]+c) {
fout << "NU\n";
return;
} else if(distante[i] == distante[vecin]+c)
egal = true;
}
if (!egal) {
fout << "NU\n";
return;
}
}
fout << "DA\n";
}
int main() {
fin >> t;
while(t--) {
citireGraf();
solve();
}
}