#include <cstdio>
#include <stack>
#include <list>
#include <set>
#include <iostream>
#include <string>
#include <vector>
#include <queue>
#include <functional>
#include <cstring>
#include <iomanip>
#include <algorithm>
#include <cctype>
#include <string>
#include <map>
#include <cmath>
using namespace std;
#define LL long long
#define ULL unsigned long long
#define SZ(x) (int)x.size()
#define Lowbit(x) ((x) & (-x))
#define MP(a, b) make_pair(a, b)
#define MS(arr, num) memset(arr, num, sizeof(arr))
#define PB push_back
#define X first
#define Y second
#define ROP freopen("input.txt", "r", stdin);
#define MID(a, b) (a + ((b - a) >> 1))
#define LC rt << 1, l, mid
#define RC rt << 1|1, mid + 1, r
#define LRT rt << 1
#define RRT rt << 1|1
#define BitCount(x) __builtin_popcount(x)
#define BitCountll(x) __builtin_popcountll(x)
#define LeftPos(x) 32 - __builtin_clz(x) - 1
#define LeftPosll(x) 64 - __builtin_clzll(x) - 1
const double PI = acos(-1.0);
const int INF = 0x3f3f3f3f;
const double eps = 1e-8;
const int MAXN = 10000 + 10;
const int MOD = 1000007;
const int dir[][2] = { {-1, 0}, {1, 0}, {0, -1}, {0, 1} };
int cases = 0;
typedef pair<int, int> pii;
typedef vector<int>::iterator viti;
typedef vector<pii>::iterator vitii;
 
vector<pair<int, double> > G[MAXN];
pair<double, double> arr[MAXN];
int n;
double maxValue[MAXN];
 
void Input()
{
    for (int i = 1; i <= n; i++) scanf("%lf%lf", &arr[i].Y, &arr[i].X);
    int nn, T;
    scanf("%d", &T);
    double rate;
    for (int i = 0; i < T; i++)
    {
        int pre, next;
        scanf("%d%d", &nn, ⪯);
        for (int j = 0; j < (nn<<1) - 2; j++)
        {
            if (!(j&1)) scanf("%lf", &rate);
            else
            {
                scanf("%d", &next);
                G[pre].PB({next, rate});
                pre = next;
            }
        }
    }
}
 
double DFS(int cur)
{
    if (maxValue[cur]) return maxValue[cur];
    double ret = arr[cur].Y;
    for (int i = 0; i < SZ(G[cur]); i++) ret = max(ret, G[cur][i].Y * DFS(G[cur][i].X));
    return maxValue[cur] = ret;
}
 
void Init()
{
    MS(maxValue, 0);
    for (int i = 1; i <= n; i++) G[i].clear();
}
 
int main()
{
    //ROP;
    int i, j;
    while (scanf("%d", &n), n)
    {
        Init();
        Input();
        for (i = 1; i <= n; i++) DFS(i);
        double ans = 0;
        for (i = 1; i <= n; i++) ans += arr[i].X * maxValue[i];
        printf("%.2f\n", ans);
    }
    return 0;
}