def dfs(nowTown,money,cost):
	if money < 0:
		return 9000000009
	if nowTown >= len(cost) - 1:
		return 0
	global dp
	if dp[nowTown][money] != -1:
		return dp[nowTown][money]
	global S,T,Y,M,connect,time
	ret = 9000000009
	for i in range(nowTown + 1,len(cost)):
		if connect[nowTown][i] != -1:
			ret = min(ret,dfs(i,money - connect[nowTown][i],cost) + time[nowTown][i])
	dp[nowTown][money] = ret
	return ret
N,C,V = int(raw_input()),int(raw_input()),int(raw_input())
S,T,Y,M = map(int,raw_input().split()),map(int,raw_input().split()),map(int,raw_input().split()),map(int,raw_input().split())
connect = [[-1 for i in range(N + 1)] for j in range(N + 1)]
time = [[-1 for i in range(N + 1)] for j in range(N + 1)]
dp = [[-1 for i in range(300 + 2)] for j in range(N + 2)]
for i in range(V):
	connect[S[i]][T[i]] = Y[i]
	connect[T[i]][S[i]] = Y[i]
	time[S[i]][T[i]] = time[T[i]][S[i]] = M[i]
cost = [9000000009 for i in range(N + 1)]
ans = dfs(1,C,cost)
if ans == 9000000009:
	print -1
else:
	print ans