import heapq

def dijkstra(n, edges, start):
    dist = [float('inf')] * n
    dist[start] = 0
    q = [(0, start)]
    while q:
        cost, u = heapq.heappop(q)
        if cost > dist[u]:
            continue
        for v, w in edges[u]:
            if cost + w < dist[v]:
                dist[v] = cost + w
                heapq.heappush(q, (dist[v], v))
    return dist

def solve():
    w, e, c = map(int, input().split())
    west = [tuple(map(int, input().split())) for _ in range(w-1)]
    east = [tuple(map(int, input().split())) for _ in range(e-1)]
    graph = [[] for _ in range(w+e)]
    for i in range(w-1):
        u, v = i+1, west[i]-1
        graph[u].append((v, 1))
        graph[v].append((u, 1))
    for i in range(e-1):
        u, v = i+1+w, east[i]-1
        graph[u].append((v, 1))
        graph[v].append((u, 1))
    # calculate the average distance of the current map
    dist = [dijkstra(w+e, graph, i) for i in range(w+e)]
    total = sum(sum(d) for d in dist)
    count = (w+e) * (w+e-1)
    avg = total / count
    res = []
    for _ in range(c):
        u, v = map(int, input().split())
        u -= 1
        v += w - 1
        # recalculate the distance between pairs of stations that include the new station
        for i in (u, v):
            dist[i] = dijkstra(w+e, graph, i)
        for i in range(w+e):
            for j in range(i+1, w+e):
                if i == u and j == v or i == v and j == u:
                    continue
                d = min(dist[i][u] + 1 + dist[v][j], dist[i][v] + 1 + dist[u][j], dist[i][j])
                total += d - dist[i][j]
                dist[i][j] = dist[j][i] = d
        count = (w+e) * (w+e-1)
        avg = total / count
        res.append(avg)
    print("Case #{}: {}".format(_t+1, " ".join("{:.6f}".format(x) for x in res)))

t = int(input())
for _t in range(t):
    solve()