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()))

r=[[] for i in range(n)]
for i in range(v):
    r[s[i]-1].append((t[i]-1,y[i],m[i]))


table=[[-1 for j in range(c+1)] for i in range(n)]
table[0][0]=0
for i in range(n):
    for j in r[i]:
        for k in range(c+1):
            if table[i][k]!=-1:
                try:
                    table[j[0]][k+j[1]]=min([table[i][k]+j[2],(table[j[0]][k+j[1]]==-1)*9999999+table[j[0]][k+j[1]]])
                except:
                    pass

if max(table[n-1])==-1:
    print(-1)
else:
    minm=1000000
    for i in range(c+1):
        if (minm>table[n-1][i])&(table[n-1][i]!=-1):
            minm=table[n-1][i]
    print(minm)