package main

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

func out(x ...interface{}) {
	fmt.Println(x...)
}

var sc = bufio.NewScanner(os.Stdin)

func getInt() int {
	sc.Scan()
	i, e := strconv.Atoi(sc.Text())
	if e != nil {
		panic(e)
	}
	return i
}

func getInts(N int) []int {
	ret := make([]int, N)
	for i := 0; i < N; i++ {
		ret[i] = getInt()
	}
	return ret
}

func getString() string {
	sc.Scan()
	return sc.Text()
}

// min, max, asub, absなど基本関数
func max(a, b int) int {
	if a > b {
		return a
	}
	return b
}

func min(a, b int) int {
	if a < b {
		return a
	}
	return b
}

func asub(a, b int) int {
	if a > b {
		return a - b
	}
	return b - a
}

func abs(a int) int {
	if a >= 0 {
		return a
	}
	return -a
}

func lowerBound(a []int, x int) int {
	idx := sort.Search(len(a), func(i int) bool {
		return a[i] >= x
	})
	return idx
}

func upperBound(a []int, x int) int {
	idx := sort.Search(len(a), func(i int) bool {
		return a[i] > x
	})
	return idx
}

func main() {
	sc.Split(bufio.ScanWords)
	na := getInt()
	a := getInts(na)
	nb := getInt()
	b := getInts(nb)

	sort.Slice(a, func(i, j int) bool {
		return a[i] > a[j]
	})
	sort.Slice(b, func(i, j int) bool {
		return b[i] > b[j]
	})

	ans := 0

	for loop := 0; loop < 2; loop++ {
		i, j, l := 0, 0, 1000
		cnt := 0
		for {
			for i < len(a) && a[i] >= l {
				i++
			}
			if i == len(a) {
				break
			}
			cnt++
			l = a[i]
			i++

			for j < len(b) && b[j] >= l {
				j++
			}
			if j == len(b) {
				break
			}
			cnt++
			l = b[j]
			j++
		}
		ans = max(ans, cnt)
		a, b = b, a
	}
	out(ans)
}