#include <bits/stdc++.h>
using namespace std;

#define INF_LL (int64)1e18
#define INF (int32)1e9
#define REP(i, n) for(int64 i = 0;i < (n);i++)
#define FOR(i, a, b) for(int64 i = (a);i < (b);i++)
#define all(x) x.begin(),x.end()
#define fs first
#define sc second

using int32 = int_fast32_t;
using uint32 = uint_fast32_t;
using int64 = int_fast64_t;
using uint64 = uint_fast64_t;
using PII = pair<int32, int32>;
using PLL = pair<int64, int64>;

const double eps = 1e-10;

template<typename A, typename B>inline void chmin(A &a, B b){if(a > b) a = b;}
template<typename A, typename B>inline void chmax(A &a, B b){if(a < b) a = b;}

template<typename T>
vector<T> make_v(size_t a){return vector<T>(a);}

template<typename T,typename... Ts>
auto make_v(size_t a,Ts... ts){
  return vector<decltype(make_v<T>(ts...))>(a,make_v<T>(ts...));
}

template<typename T,typename U,typename... V>
typename enable_if<is_same<T, U>::value!=0>::type
fill_v(U &u,const V... v){u=U(v...);}

template<typename T,typename U,typename... V>
typename enable_if<is_same<T, U>::value==0>::type
fill_v(U &u,const V... v){
  for(auto &e:u) fill_v<T>(e,v...);
}

template<::std::uint_fast64_t mod>
class ModInt{
private:
    using value_type = ::std::uint_fast64_t;
    value_type n;
public:
    ModInt() : n(0) {}
    ModInt(value_type n_) : n(n_ % mod) {}
    ModInt(const ModInt& m) : n(m.n) {}

    template<typename T>
    explicit operator T() const { return static_cast<T>(n); }
    value_type get() const { return n; }

    friend ::std::ostream& operator<<(::std::ostream &os, const ModInt<mod> &a) {
        return os << a.n;
    }

    friend ::std::istream& operator>>(::std::istream &is, ModInt<mod> &a) {
        value_type x;
        is >> x;
        a = ModInt<mod>(x);
        return is;
    }

    bool operator==(const ModInt& m) const { return n == m.n; }
    bool operator!=(const ModInt& m) const { return n != m.n; }
    ModInt& operator*=(const ModInt& m){ n = n * m.n % mod; return *this; }

    ModInt pow(value_type b) const{
        ModInt ans = 1, m = ModInt(*this);
        while(b){
            if(b & 1) ans *= m;
            m *= m;
            b >>= 1;
        }
        return ans;
    }

    ModInt inv() const { return (*this).pow(mod-2); }
    ModInt& operator+=(const ModInt& m){ n += m.n; n = (n < mod ? n : n - mod); return *this; }
    ModInt& operator-=(const ModInt& m){ n += mod - m.n; n = (n < mod ? n : n - mod); return *this; }
    ModInt& operator/=(const ModInt& m){ *this *= m.inv(); return *this; }
    ModInt operator+(const ModInt& m) const { return ModInt(*this) += m; }
    ModInt operator-(const ModInt& m) const { return ModInt(*this) -= m; }
    ModInt operator*(const ModInt& m) const { return ModInt(*this) *= m; }
    ModInt operator/(const ModInt& m) const { return ModInt(*this) /= m; }
    ModInt& operator++(){ n += 1; return *this; }
    ModInt& operator--(){ n -= 1; return *this; }
    ModInt operator++(int){
        ModInt old(n);
        n += 1;
        return old;
    }
    ModInt operator--(int){
        ModInt old(n);
        n -= 1;
        return old;
    }
    ModInt operator-() const { return ModInt(mod-n); }
};

constexpr int64 mod = 1e9+7;
using Mint = ModInt<mod>;

string S, T;
int64 N;
vector<vector<pair<Mint, Mint>>> dp;
vector<vector<int>> used;
vector<Mint> ten;

using PMM = pair<Mint, Mint>;

PMM dfs(int64 dig = 0, bool tight = 1) {
    if (used[dig][tight]) return dp[dig][tight];
    if (dig == N) return PMM(1, 0);
    used[dig][tight] = 1;
    PMM &res = dp[dig][tight];
    res = PMM(0, 0);

    int64 lim = tight ? S[dig]-'0' : 9;
    if (T[dig] == '?') {
        for (int64 i = 0; i <= lim; i++) {
            Mint val = ten[dig] * i;
            PMM ret = dfs(dig+1, tight && (lim == i));
            res.fs += ret.fs;
            res.sc += ret.sc + ret.fs * val;
        }
    } else {
        if (lim < T[dig]-'0') return PLL(0, 0);
        Mint val = ten[dig] * (T[dig]-'0');
        PMM ret = dfs(dig + 1, tight && (lim == T[dig] - '0'));
//        cout << dig << " " << ret.fs << " " << ret.sc << " " << val << endl;
        res.fs += ret.fs;
        res.sc += ret.sc + ret.fs * val;
    }
    return res;
}

int main(void){
	cin.tie(0);
	ios::sync_with_stdio(false);
	cin >> S >> T;
	N = S.size();
	dp = make_v<PMM>(N+1, 2);
	used = make_v<int>(N+1, 2);
	ten = vector<Mint>(N+1, 0);
	ten[N-1] = 1;
	for (int64 i = N-2; i >= 0; i--) {
	    ten[i] = ten[i+1] * 10;
	}
	fill_v<int>(used, 0);
	cout << dfs().sc << endl;
}



Measured memory_bytes: 48700