import heapq

n=int(input())
c=int(input())
v=int(input())
u=list(map(int,input().split()))
w=list(map(int,input().split()))
x=list(map(int,input().split()))
m=list(map(int,input().split()))
a=[[] for i in range(n)]
for i in range(v):
	a[u[i]-1].append([w[i]-1,x[i],m[i]])
dp=[[10**9]*(c+1) for i in range(n)]
x=[]
heapq.heappush(x,[0,c,0])
while len(x):
	q,w,e=heapq.heappop(x)
	if dp[e][w]!=10**9:
		continue
	dp[e][w]=q
	for i,j,l in a[e]:
		if w-j<0:
			continue
		heapq.heappush(x,[q+l,w-j,i])
x=min(dp[-1])
if x==10**9:
	x=-1
print(x)