from bisect import bisect_left
from operator import add, mul, sub, truediv


def main():
    N, M, K = map(int, input().split())

    op, *B = input().split()
    B = list(map(int, B))
    B.sort()
    A = [int(input()) for _ in range(N)]
    A.sort()

    match op:
        case "+":
            op_func = sub
        case "*":
            op_func = truediv
        case _:
            raise ValueError

    ctr = 0
    b_idx = None
    for row, a_elm in enumerate(A):
        b_idx = bisect_left(B, op_func(K, a_elm), hi=b_idx)
        ctr += len(B) - b_idx
    print(ctr)


if __name__ == "__main__":
    main()