package main

import (
	"fmt"
	"bufio"
	"os"
	"sort"
)

func main() {
	r := bufio.NewReader(os.Stdin)
	w := bufio.NewWriter(os.Stdout)
	defer w.Flush()
	var N, M, K int
	fmt.Fscan(r, &N, &M, &K)
	var op string
	fmt.Fscan(r, &op)
	var opfunc func(int, int) int
	if op == "+" {
		opfunc = add
	} else {
		opfunc = mul
	}
	B := make([]int, M)
	for i := 0; i < M; i++ {
		fmt.Fscan(r, &B[i])
	}
	sort.Ints(B)
	A := make([]int, N)
	for i := 0; i < N; i++ {
		fmt.Fscan(r, &A[i])
	}
	sort.Ints(A)
	cnt := 0
	j := M - 1
	for i := 0; i < N; i++ {
		for j >= 0 {
			if calc(A[i], B[j], opfunc) < K {
				break
			}
			j--
		}
		cnt += M - 1 - j
	}
	fmt.Fprintln(w, cnt)
}

func calc(a int, b int, calcfunc func(int, int) int) int {
	return calcfunc(a, b)
}

func add(a int, b int) int {
	return a + b
}

func mul(a int, b int) int {
	return a * b
}