N,M,K=map(int,input().split())
A=[]
B=[i for i in input().split()]
C=0
for i in range(N):
    a=int(input())
    A.append(a)
if B[0]=="+":
    for i in range(N):
        for j in range(1,M+1):
            C+=A[i]+int(B[j])
elif B[0]=="*":
    for i in range(N):
        for j in range(1,M+1):
            C+=A[i]*int(B[j])
x,y=divmod(C,K)
print(y)