N = input()
C = input()
V = input()

def func(x):
    return int(x) - 1

S = map(func,raw_input().split())
T = map(func,raw_input().split())
Y = map(int,raw_input().split())
M = map(int,raw_input().split())

LT = [[] for i in range(N)]
LY = [[] for i in range(N)]
LM = [[] for i in range(N)]

for i in range(V):
    LT[S[i]].append(T[i])
    LY[S[i]].append(Y[i])
    LM[S[i]].append(M[i])

INF=99999999
DP = [[INF for i in range(C+1)] for j in range(N)]
DP[0][0] = 0

for i in range(N):
    for j in range(C+1):
        if DP[i][j] != INF:
            for k in range(len(LT[i])):
                if j+LY[i][k] <=C:
                    DP[LT[i][k]][j+LY[i][k]] = min(DP[LT[i][k]][j+LY[i][k]],DP[i][j]+LM[i][k])
min = INF
flag = False

for i in range(C+1):
    if(DP[N-1][i]<min):
        min=DP[N-1][i]
        flag=True
if flag:
    print min
else:
    print -1