#include <iostream>
//by GB Zaleski
using namespace std;
#define MAXVAL 1000000

int Array[MAXVAL];
int Counter[MAXVAL];
int recCounter;
int result;
int length;
int n,m;

struct desc
{
    int val = 0;
    int ile = 0;
};

int main()
{
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    cout.tie(0);
    recCounter = 0;
    result = 0;
    length = 0;
    for (int i=0; i!= MAXVAL; ++i) Counter[i] = 0;
    cin >> n >> m;
    recCounter = m;
    desc Proceed[m];
    for (int i=0; i!=m; ++i)
    {
        cin >> Proceed[i].ile;
        length += Proceed[i].ile;
    }
    for (int i=0; i!=m; ++i) cin >> Proceed[i].val;
    for (int i=0; i!=m; ++i) Counter[Proceed[i].val] = Proceed[i].ile;
    for (int i=0; i!=n; ++i) cin >> Array[i];

    for (int i=0; i!=length; ++i)
    {
        Counter[Array[i]]--;
        if (Counter[Array[i]] == 0)
        {
            recCounter--;
            if (recCounter == 0) result++;
        }
        else if (Counter[Array[i]] == -1) recCounter++;
        /*for (int i=0; i!=6; ++i) cout << Counter[i] << " ";
        cout << " -> rC =" << recCounter;
        cout << endl;*/
    }

    //cout << "Part2\n";
    for (int i=length; i!=n ; ++i)
    {
        Counter[Array[i-length]]++;
        if (Counter[Array[i-length]] == 0)
        {
            recCounter--;
            if (recCounter == 0) result++;
        }
        else if (Counter[Array[i]] == 1) recCounter++;

        Counter[Array[i]]--;
        if (Counter[Array[i]] == 0)
        {
            recCounter--;
            if (recCounter == 0) result++;
        }
        else if (Counter[Array[i]] == -1) recCounter++;

        /* for (int i=0; i!=6; ++i) cout << Counter[i] << " ";
         cout << " -> rC =" << recCounter;
         cout << endl;*/
    }


    cout << result;
    return 0;
}

/*
7 3
2 1 1
1 2 3
1 1 2 3 3 3 3
*/