#!/usr/bin/env python3
# -*- coding: utf-8-*-
import numpy as np
if __name__ == '__main__':
    INF = 10000000
    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(" ")))
    vl = [ [] for i in range(n)]
    for i in range(v):
        vl[s[i]-1].append((t[i]-1, y[i], m[i]))
    t = np.full((n, c+1), INF)
    t[0,0] = 0
    for i in range(n):
        for j in range(c+1):
            if t[i, j] == INF:
                continue
            for tt, yy, mm in vl[i]:
                if j+yy <= c:
                    t[tt, j+yy] = min(t[i, j] + mm, t[tt, j+yy])
    a = min(t[n-1, :])
    if a == INF:
        a = -1
    print(a)