#include <bits/stdc++.h>
#pragma GCC optimize("Ofast,no-stack-protector")
#pragma GCC target("avx")
using namespace std;
template <typename T, typename U>
inline void smin(T &a, U b) {
  if (a > b) a = b;
}
template <typename T, typename U>
inline void smax(T &a, U b) {
  if (a < b) a = b;
}
template <class T>
inline void gn(T &first) {
  char c, sg = 0;
  while (c = getchar(), (c > '9' || c < '0') && c != '-')
    ;
  for ((c == '-' ? sg = 1, c = getchar() : 0), first = 0; c >= '0' && c <= '9';
       c = getchar())
    first = (first << 1) + (first << 3) + c - '0';
  if (sg) first = -first;
}
template <class T>
inline void print(T first) {
  if (first < 0) {
    putchar('-');
    return print(-first);
  }
  if (first < 10) {
    putchar('0' + first);
    return;
  }
  print(first / 10);
  putchar(first % 10 + '0');
}
template <class T, class T1>
inline void gn(T &first, T1 &second) {
  gn(first);
  gn(second);
}
template <class T, class T1, class T2>
inline void gn(T &first, T1 &second, T2 &z) {
  gn(first);
  gn(second);
  gn(z);
}
template <class T>
inline void println(T first) {
  print(first);
  putchar('\n');
}
template <class T>
inline void printsp(T first) {
  print(first);
  putchar(' ');
}
template <class T1, class T2>
inline void print(T1 x1, T2 x2) {
  printsp(x1), println(x2);
}
template <class T1, class T2, class T3>
inline void print(T1 x1, T2 x2, T3 x3) {
  printsp(x1), printsp(x2), println(x3);
}
template <class T1, class T2, class T3, class T4>
inline void print(T1 x1, T2 x2, T3 x3, T4 x4) {
  printsp(x1), printsp(x2), printsp(x3), println(x4);
}
int power(int a, int b, int m, int ans = 1) {
  for (; b; b >>= 1, a = 1LL * a * a % m)
    if (b & 1) ans = 1LL * ans * a % m;
  return ans;
}
int a[100011];
double dp[100011][111];
int n;
double C[100011 * 10][6];
int b[100011];
void solve() {
  for (int i = 0; i < 100011; i++) {
    C[i][0] = 1;
    for (int j = 1; j <= i and j <= 5; j++)
      C[i][j] = (C[i - 1][j - 1] + C[i - 1][j]);
  }
  cin >> n;
  double ans = 0;
  for (int i = 1; i <= n; i++) {
    gn(a[i]);
    b[i] = a[i];
    dp[i][a[i]] = 1;
    if (a[i] == 0) ans++;
  }
  int q;
  gn(q);
  int u, v, k;
  double tmp = 0;
  while (q--) {
    gn(u);
    gn(v);
    gn(k);
    ans -= dp[u][0];
    for (int i = 0; i <= b[u]; i++) {
      tmp = 0;
      for (int j = i; j <= i + k; j++) {
        tmp += dp[u][j] * C[j][j - i] * C[a[u] - j][k - j + i] / C[a[u]][k];
      }
      dp[u][i] = tmp;
    }
    ans += dp[u][0];
    a[v] += k;
    a[u] -= k;
    printf("%.10lf\n", ans);
  }
}
int main() {
  solve();
  return 0;
}
