3
1 1 5
1 3 42
1 2 42
 2
42 23
1 2 10
 10
45792697 27183921 4791060 77070594 27286110 66957065 19283638 2944837 26775511 65379701
5 8 25
8 10 94
1 4 14
9 7 96
4 2 16
2 6 58
2 3 99
6 8 21
8 9 87
 5
3 1 2 6 5
1 2 3
2 3 1
4 3 9
5 3 1
 10
26 31 21 57 56 44 54 58 79 97
2 1 277
1 8 91
1 7 380
4 1 649
10 5 799
10 1 940
8 6 627
6 3 177
9 6 685
 10
8 100 62 38 26 51 26 23 77 32
6 8 29
4 1 82
7 8 66
7 10 67
8 9 98
6 1 14
1 5 48
3 1 58
2 9 90
 2
23 42
1 2 10
 1
42
 3
1 5 1
1 3 42
1 2 42
 10
1 1 1 1 1 1 1 1 1 1
1 2 5
1 3 5
1 4 5
1 5 5
1 6 5
1 7 5
1 8 5
1 9 5
1 10 5
 3
1 1 1
1 2 42
2 3 42
 3
5 1 1
1 3 42
1 2 24

3 1042.0638260857 1 727.3238618387 6 283959805416.40496826
 3 192.0000000000 1 13952642.4776933547 8 544327.1927847408 2 727.3238618387 1 0.0000000000 2 1042.0638260857 1 100.6230589875 2 544.3822186663 1 389.7666169867
#include <bits/stdc++.h>
using namespace std;
struct e {
  int to;
  double val;
  e(int t = 0, double v = 0) : to(t), val(v) {}
};
vector<e> ed[400000];
double w[400000];
int sz[400000], maxsz[400000];
double dis[400000];
bool ban[400000];
vector<int> all_nd;
void dfs_bas(int u, int f) {
  if (ban[u]) return;
  all_nd.push_back(u);
  sz[u] = 1, maxsz[u] = 0;
  int maxv = 0;
  for (int i = 0; i < ed[u].size(); i++) {
    int v = ed[u][i].to;
    if (v == f) continue;
    dfs_bas(v, u);
    sz[u] += sz[v];
    maxsz[u] = max(maxsz[u], sz[v]);
  }
}
double der[400000];
double dfs_calc(int u, int f) {
  der[u] = w[u] * 1.5 * pow(dis[u], 0.5);
  double sum = w[u] * pow(dis[u], 1.5);
  for (int i = 0; i < ed[u].size(); i++) {
    int v = ed[u][i].to;
    if (v == f) continue;
    dis[v] = dis[u] + ed[u][i].val;
    sum += dfs_calc(v, u);
    der[u] += der[v];
  }
  return sum;
}
double ans;
int pos;
void work(int u) {
  int rt = 0;
  all_nd.clear();
  dfs_bas(u, 0);
  for (int i = 0; i < all_nd.size(); i++)
    if (max(sz[u] - sz[all_nd[i]], maxsz[all_nd[i]]) - 1 <= (sz[u] >> 1))
      rt = all_nd[i];
  dis[rt] = 0;
  double sum = dfs_calc(rt, 0);
  if (ans > sum) {
    ans = sum, pos = rt;
  }
  ban[rt] = 1;
  double sumd = der[rt];
  printf("%d %d\n", u, rt);
  for (int i = 0; i < ed[rt].size(); i++) {
    int v = ed[rt][i].to;
    if (!ban[v] && sumd - 2 * der[v] < 0) {
      work(v);
      break;
    }
  }
}
int main() {
  int n = 0;
  scanf("%d", &n);
  for (int i = 1; i <= n; i++) scanf("%lf", &w[i]);
  for (int i = 1, x = 0, y = 0; i < n; i++) {
    double v = 0;
    scanf("%d%d%lf", &x, &y, &v);
    ed[x].push_back(e(y, v)), ed[y].push_back(e(x, v));
  }
  ans = 1e18;
  work(1);
  printf("%d %.10lf", pos, ans);
  return 0;
}
