#include <iostream>
#include <vector>
#include <stack>
#include <algorithm>
using namespace std;

int n, m, x, uniq, minA, minB;
struct element
{
    int val;
    int pos;
};

stack <element> st;

vector <int> frec (1024);
vector <int> a;

void popStack()
{
    element e = st.top();
    a[e.pos] = -100;
    st.pop();
}

int main()
{
    cin >> n >> m;
    for(int i = 0; i < n; i++)
    {
        cin >> x;
        if(x < minA)
            minA = x;
        a.push_back(x);
    }


    for(int i = 0; i < n; i++)
    {
        int x = a[i] - minA;
        if(!frec[x])
        {
            frec[x] = 1;
            uniq++;
        }
        else
        {
            element e;
            e.val = x;
            e.pos = i;
            st.push(e);
        }
    }

    for(int i = 0; i < m && !st.empty(); i++)
    {
        cin >> x;
        popStack();
    }

    cout << uniq << endl;
    for(int i = 0; i < n; i++)
    {
        if(a[i] != -100)
        {
            cout << a[i] << " ";
        }
    }
    return 0;
}