#include <bits/stdc++.h>
using namespace std;
template <typename T>
inline T gi() {
  T x = 0, f = 1;
  char c = getchar();
  while (c < '0' || c > '9') {
    if (c == '-') f = -1;
    c = getchar();
  }
  while (c >= '0' && c <= '9') x = x * 10 + c - '0', c = getchar();
  return f * x;
}
const int N = 100003, M = N << 1;
int n, q, a[N], b[N];
double C[1000003][6];
double dp[N][113];
inline void pre() {
  C[0][0] = C[1][0] = C[1][1] = 1.0;
  for (int i = 2; i <= 1000000; i += 1) {
    C[i][0] = 1.0;
    for (int j = 1; j <= min(i, 5); j += 1)
      C[i][j] = C[i - 1][j] + C[i - 1][j - 1];
  }
}
int main() {
  n = gi<int>();
  double ans = 0.0;
  for (int i = 1; i <= n; i += 1)
    a[i] = b[i] = gi<int>(), dp[i][a[i]] = 1.0, ans += dp[i][0];
  pre();
  q = gi<int>();
  while (q--) {
    int u = gi<int>(), v = gi<int>(), k = gi<int>();
    ans -= dp[u][0];
    double q = C[a[u]][k];
    for (int i = 0; i <= b[u]; i += 1) {
      double tmp = 0.0;
      for (int j = 0; j <= min(k, a[u] - i); j += 1)
        tmp += dp[u][i + j] * C[i + j][j] * C[a[u] - i - j][k - j];
      dp[u][i] = tmp / q;
    }
    a[u] -= k, a[v] += k;
    ans += dp[u][0];
    printf("%.10lf\n", ans);
  }
  return 0;
}
