import os
import sys
from io import BytesIO, IOBase
import numpy as np
import queue
from copy import deepcopy

def get_distance_array(edge_list):
    edge_map=dict()
    for i in range(len(edge_list)):
        edge_list[i]=int(edge_list[i])-1
        
    for i in range(len(edge_list)):
        if i not in edge_map:
            edge_map[i] = [edge_list[i]]
        else:
            edge_map[i].append(edge_list[i])
        if edge_list[i] not in edge_map:
            edge_map[edge_list[i]] = [i]
        else:
            edge_map[edge_list[i]].append(i)

    distance_array = [[len(edge_list)]*(len(edge_list)+1) for i in range(len(edge_list)+1)]
    Q = queue.Queue()
    visited_vertices = set()
    Q.put(0)
    visited_vertices.update({0})
    while not Q.empty():
        i = Q.get()
        distance_array[i][i]=0
        for u in edge_map[i]:
            distance_array[i][u] = 1
            distance_array[u][i] = distance_array[i][u] 
            if u not in visited_vertices:
                for vi in visited_vertices:
                    if vi != i and vi != u:
                        distance_array[vi][u] =  distance_array[vi][i] + 1
                        distance_array[u][vi] = distance_array[vi][u] 
                Q.put(u)
                visited_vertices.update({u})
    return distance_array
        
        

def main():
    for t in range(int(input())):
        w,e,c = map(int,input().split())
        x_list = input().split()
        f_list = input().split()
        x_da = get_distance_array(x_list)
        f_da = get_distance_array(f_list)
        norm=(len(x_list)+len(f_list)+2)*(len(x_list)+len(f_list)+1)/2
        tempsum=np.sum(x_da)/2+ np.sum(f_da)/2 + (len(x_list)+1)*(len(f_list)+1)
        result = []
        for ci in range(c):
            a,b = map(int,input().split())
            result.append((tempsum+np.sum(x_da[a-1])*(len(f_list)+1)+np.sum(f_da[b-1])*(len(x_list)+1))/norm)
        prints= "Case #" +str(t + 1)+":"    
        for value in result:
            prints += " "+str(value)
        print(prints)

# region fastio

BUFSIZE = 8192


class FastIO(IOBase):
    newlines = 0

    def __init__(self, file):
        self._file = file
        self._fd = file.fileno()
        self.buffer = BytesIO()
        self.writable = "x" in file.mode or "r" not in file.mode
        self.write = self.buffer.write if self.writable else None

    def read(self):
        while True:
            b = os.read(self._fd, max(os.fstat(self._fd).st_size, BUFSIZE))
            if not b:
                break
            ptr = self.buffer.tell()
            self.buffer.seek(0, 2), self.buffer.write(b), self.buffer.seek(ptr)
        self.newlines = 0
        return self.buffer.read()

    def readline(self):
        while self.newlines == 0:
            b = os.read(self._fd, max(os.fstat(self._fd).st_size, BUFSIZE))
            self.newlines = b.count(b"\n") + (not b)
            ptr = self.buffer.tell()
            self.buffer.seek(0, 2), self.buffer.write(b), self.buffer.seek(ptr)
        self.newlines -= 1
        return self.buffer.readline()

    def flush(self):
        if self.writable:
            os.write(self._fd, self.buffer.getvalue())
            self.buffer.truncate(0), self.buffer.seek(0)


class IOWrapper(IOBase):
    def __init__(self, file):
        self.buffer = FastIO(file)
        self.flush = self.buffer.flush
        self.writable = self.buffer.writable
        self.write = lambda s: self.buffer.write(s.encode("ascii"))
        self.read = lambda: self.buffer.read().decode("ascii")
        self.readline = lambda: self.buffer.readline().decode("ascii")


sys.stdin, sys.stdout = IOWrapper(sys.stdin), IOWrapper(sys.stdout)
input = lambda: sys.stdin.readline().rstrip("\r\n")

# endregion

if __name__ == "__main__":
    main()