#include <bits/stdc++.h>

#define ll long long

#define mp make_pair

#define x first

#define y second

using namespace std;

const int maxn = 2e5+;

const ll mod = ;

ll fac[maxn];

ll rea[maxn];

ll ans1,ans2;

char a[maxn];

char b[maxn];

int main()

{

    //freopen("in.txt","r",stdin);

    ll n,m;

    scanf("%lld%lld",&n,&m);

    scanf("%s %s",a,b);

    fac[] = ;

    for(int i = ; i < n; ++i){

        fac[i] = *fac[i-]%mod;

    }

    for(int i = ; i < n/; ++i)

    {

        swap(a[i],a[n--i]);

    }

    for(int i = ; i < m/; ++i)

    {

        swap(b[i],b[m--i]);

    }

    rea[] = ;

    if(a[] == '')

        rea[] = ;

    for(int i = ; i < n; ++i)

    {

        rea[i] = rea[i-];

        if(a[i] == '')

            rea[i] = (rea[i]+fac[i]);

    }

    for(int i = ; i < n; ++i)

    {

        if(a[] == '')

            ans1 = (ans1 + rea[i])%mod;

    }

    ll ans = ;

    for(int i = ; i < n && i < m; ++i)

    {

        if(b[i] == '')

        {

            ans = (ans+rea[i])%mod;

        }

    }

    for(int i = n; i < m; ++i)

    {

        if(b[i] == '')

            ans = (ans+rea[n-])%mod;

    }

    cout << ans << endl;

}