import collections
import math
range = xrange; input = raw_input


class Dinic:
    """Dinic Algorithm: find max-flow
       complexity: O(EV^2)
       used in GRL6A(AOJ)
    """
    class edge:
        def __init__(self, to, cap, rev):
            self.to, self.cap, self.rev = to, cap, rev

    def __init__(self, V, E, source, sink):
        """ V: the number of vertexes
            E: adjacency list
            source: start point
            sink: goal point
        """
        self.V = V
        self.E = [[] for _ in range(V)]
        for fr in range(V):
            for to, cap in E[fr]:
                self.E[fr].append(self.edge(to, cap, len(self.E[to])))
                self.E[to].append(self.edge(fr, 0, len(self.E[fr])-1))
        self.maxflow = self.dinic(source, sink)

    def dinic(self, source, sink):
        """find max-flow"""
        INF = float('inf')
        maxflow = 0
        while True:
            self.bfs(source)
            if self.level[sink] < 0:
                return maxflow
            self.itr = [0] * self.V
            while True:
                flow = self.dfs(source, sink, INF)
                if flow > 0:
                    maxflow += flow
                else:
                    break

    def dfs(self, vertex, sink, flow):
        """find augmenting path"""
        if vertex == sink:
            return flow
        for i in range(self.itr[vertex], len(self.E[vertex])):
            self.itr[vertex] = i
            e = self.E[vertex][i]
            if e.cap > 0 and self.level[vertex] < self.level[e.to]:
                d = self.dfs(e.to, sink, min(flow, e.cap))
                if d > 0:
                    e.cap -= d
                    self.E[e.to][e.rev].cap += d
                    return d
        return 0

    def bfs(self, start):
        """find shortest path from start"""
        que = collections.deque()
        self.level = [-1] * self.V
        que.append(start)
        self.level[start] = 0

        while que:
            fr = que.popleft()
            for e in self.E[fr]:
                if e.cap > 0 and self.level[e.to] < 0:
                    self.level[e.to] = self.level[fr] + 1
                    que.append(e.to)

while True:
    M, N = map(int, input().split())
    if M == 0 and N == 0:
        break
    blue, red = [], []
    while True:
        for x in input().split():
            blue.append(int(x))
        if len(blue) == M:
            break
    while True:
        for x in input().split():
            red.append(int(x))
        if len(red) == N:
            break
    V = M + N + 2
    edge = [set() for _ in range(V)]
    for i, b in enumerate(blue):
        if b != 1:
            for j, r in enumerate(red):
                if r % b == 0:
                    edge[i].add((M+j, 1))
        for j in range(2, int(math.sqrt(b)) + 1):
            if b % j == 0:
                for k, r in enumerate(red):
                    if r % j == 0 or r % (b // j) == 0:
                        edge[i].add((M+k, 1))
    for i in range(M):
        edge[M+N].add((i, 1))
    for j in range(N):
        edge[M+j].add((M+N+1, 1))
    d = Dinic(V, edge, M+N, M+N+1)
    print(d.maxflow)

Measured memory_bytes: 188428