nw = gets.to_i
w = gets.split.map(&:to_i)
nb = gets.to_i
b = gets.split.map(&:to_i)
w.sort!{|a, b| b <=> a}
b.sort!{|a, b| b <=> a}
wi = 0
bi = 0
block = 21
c1 = 0
while true do
    while wi < nw
        if w[wi] < block
            block = w[wi]
            c1 += 1
            break
        end
        wi += 1
    end
    break if wi >= nw
    wi += 1
    while bi < nb
        if b[bi] < block
            block = b[bi]
            c1 += 1
            break
        end
        bi += 1
    end
    break if bi >= nb
    bi += 1
end
wi = 0
bi = 0
block = 21
c2 = 0
while true do
    while bi < nb
        if b[bi] < block
            block = b[bi]
            c2 += 1
            break
        end
        bi += 1
    end
    break if bi >= nb
    bi += 1
    while wi < nw
        if w[wi] < block
            block = w[wi]
            c2 += 1
            break
        end
        wi += 1
    end
    break if wi >= nw
    wi += 1
end
puts (c1 > c2) ? c1 : c2