#include <bits/stdc++.h>
using namespace std;
inline int read() {
  int s = 0, w = 1, ch = getchar();
  while (!isdigit(ch)) {
    if (ch == '-') w = -1;
    ch = getchar();
  }
  while (isdigit(ch)) {
    s = (s << 3) + (s << 1) + ch - 48;
    ch = getchar();
  }
  return s * w;
}
const int maxn = 1e5 + 50;
int n, Q, a[maxn], now[maxn];
double f[maxn][250], C[5050][10];
signed main() {
  double ans = 0;
  n = read();
  for (int i = 1; i <= n; i++) a[i] = read(), now[i] = a[i];
  Q = read();
  for (int i = 1; i <= n; i++) f[i][a[i]] = 1;
  for (int i = 1; i <= n; i++) ans += f[i][0];
  C[0][0] = 1;
  C[1][0] = C[1][1] = 1;
  for (int i = 2; i <= 5049; i++) {
    C[i][0] = 1;
    for (int j = 1; j <= min(i, 5); j++)
      C[i][j] = C[i - 1][j] + C[i - 1][j - 1];
  }
  while (Q--) {
    int u = read(), v = read(), w = read();
    ans -= f[u][0];
    for (int i = 0; i <= a[u]; i++) {
      double res = 0;
      for (int j = i; j <= min(i + w, now[u]); j++) {
        res += f[u][j] * C[j][j - i] * C[now[u] - j][w + i - j];
      }
      res /= 1.0 * C[now[u]][w];
      f[u][i] = res;
    }
    ans += f[u][0];
    now[u] -= w;
    now[v] += w;
    printf("%0.12lf\n", ans);
  }
  return 0;
}
