def dfs(s,y,m):
    global cost_time
    if s == N-1:
        cost_time.append((y,m))
    for to, cost, time in adj[s]:
        if y + cost <= C:
            dfs(to,y+cost,m+time)
                
# 入力の受け取り・隣接リストadjの構築：
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()))

adj = [[] for _ in range(N)]
for i in range(V):
    adj[S[i]-1].append((T[i]-1, Y[i], M[i]))

cost_time = []
dfs(0,0,0)

ans = float("INF")
for cost,time in cost_time:
    if cost <= C:
        ans = min(ans,time)
ans = -1 if ans == float("INF") else ans
print(ans)