from collections import deque

N = int(input())
C = int(input())
V = int(input())

Sori = list(map(int,input().split()))
Tori = list(map(int,input().split()))
Yori = list(map(int,input().split()))
Mori = list(map(int,input().split()))

dic = {}

for i in range(V):

    s = Sori[i]-1
    t = Tori[i]-1

    y = Yori[i]
    m = Mori[i]

    if s not in dic:
        dic[s] = []

    dic[s].append([t,y,m])


lis = [[float("inf")] * (C+1) for i in range(N) ]
lis[0][0] = 0

q = deque([])
q.append([0,0])

while len(q) > 0:

    now = q.popleft()
    np = now[0]
    nc = now[1]

    if np not in dic:
        continue

    for i in dic[np]:

        nexp = i[0]
        nexc = i[1]
        dis = i[2]

        if nc + nexc <= C:

            if lis[nexp][nc+nexc] > lis[np][nc] + dis:
                lis[nexp][nc+nexc] = lis[np][nc] + dis
                q.append([nexp,nc+nexc])

ans = float("inf")
#print (lis[-1])

for i in range(C+1):

    ans = min(ans , lis[-1][i])

if ans == float("inf"):
    print (-1)
else:
    print (ans)