import sys
from bisect import bisect_right


def input(): return sys.stdin.readline().rstrip('\n')


def main():
    n, m, k = map(int, input().split())
    op, *b = input().split()
    *b, = sorted(map(int, b))
    ans = 0
    for _ in range(n):
        a = int(input())
        targ = (k - 1) // a if op == '*' else k - 1 - a
        ans += m - bisect_right(b, targ)

    return ans


if __name__ == '__main__':
    ret = main()
    if ret is not None:
        print(ret)