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