#!/usr/bin/env PyPy3

from collections import Counter, defaultdict, deque
import itertools
import re
import math
from functools import reduce
import operator
import bisect
from heapq import *
import functools
import typing
mod=998244353

import sys
input = sys.stdin.readline
import typing
INF = 1 << 31
n = int(input())
c = int(input())
v = int(input())
s = list(map(int,input().split()))
t = list(map(int,input().split()))
y = list(map(int,input().split()))
m = list(map(int,input().split()))
g = [[] for _ in range(n)]
for i in range(v):
    g[s[i] - 1].append([t[i] - 1,y[i],m[i]])
dp = [[INF] * (c + 1) for _ in range(n)]
dp[0][0] = 0
for i in range(n):
    for cc in range(c + 1):
        if dp[i][cc] == INF:continue
        for j,cost,mm in g[i]:
            if cc + cost <= c:
                dp[j][cc + cost] = min(dp[j][cc + cost],dp[i][cc] + mm)
ans = min(dp[-1])
if ans == INF:
    print(-1)
else:
    print(ans)