#include #include #include #include using namespace std; using i64 = long long; class range {private: struct I{int x;int operator*(){return x;}bool operator!=(I& lhs){return x a; int sign; bigint(void); bigint(long long); bigint(const string&); void operator = (const bigint&); void operator = (long long); bigint operator + (const bigint&) const; bigint operator - () const; bigint operator - (const bigint&) const; bigint operator * (int v) const; bigint operator * (const bigint&) const; bigint operator / (int) const; bigint operator / (const bigint&) const; int operator % (int) const; bigint operator % (const bigint&) const; friend pair divmod(const bigint&, const bigint&); void operator += (const bigint&); void operator -= (const bigint&); void operator *= (int v); void operator *= (const bigint&); void operator /= (int); void operator /= (const bigint&); bool operator < (const bigint&) const; bool operator > (const bigint&) const; bool operator <= (const bigint&) const; bool operator >= (const bigint&) const; bool operator == (const bigint&) const; bool operator != (const bigint&) const; bigint abs() const; bool isZero(void) const; long long longValue() const; friend bigint gcd(const bigint&, const bigint&); friend bigint lcm(const bigint&, const bigint&); bigint pow(int) const; void trim(void); void read(const string&); friend istream& operator >> (istream&, bigint&); friend ostream& operator << (ostream&, const bigint&); static vector convert_base(const vector&, int, int); static vector karatsubaMultiply(const vector&, const vector&); }; bigint::bigint() : sign(1) {} bigint::bigint(long long v) { *this = v; } bigint::bigint(const string &s) { read(s); } void bigint::operator=(const bigint &v) { sign = v.sign; a = v.a; } void bigint::operator=(long long v) { sign = 1; if(v < 0) { sign = -1, v = -v; } for(; v > 0; v = v / base) { a.push_back(v % base); } } bigint bigint::operator+(const bigint &v) const { if(sign != v.sign) { return *this - (-v); } bigint res = v; for(int i = 0, carry = 0; i < (int) max(a.size(), v.a.size()) || carry; ++i) { if(i == (int) res.a.size()) { res.a.push_back(0); } res.a[i] += carry + (i < (int) a.size() ? a[i] : 0); carry = res.a[i] >= base; if(carry) { res.a[i] -= base; } } return res; } bigint bigint::operator-(const bigint &v) const { if(sign != v.sign) { return *this + (-v); } if(abs() < v.abs()) { return -(v - *this); } bigint res = *this; for(int i = 0, carry = 0; i < (int) v.a.size() || carry; ++i) { res.a[i] -= carry + (i < (int) v.a.size() ? v.a[i] : 0); carry = res.a[i] < 0; if(carry) { res.a[i] += base; } } res.trim(); return res; } void bigint::operator*=(int v) { if(v < 0) { sign = -sign, v = -v; } for(int i = 0, carry = 0; i < (int) a.size() || carry; ++i) { if(i == (int) a.size()) { a.push_back(0); } long long cur = a[i] * (long long) v + carry; carry = (int) (cur / base); a[i] = (int) (cur % base); //asm("divl %%ecx" : "=a"(carry), "=d"(a[i]) : "A"(cur), "c"(base)); } trim(); } bigint bigint::operator*(int v) const { bigint res = *this; res *= v; return res; } pair divmod(const bigint &a1, const bigint &b1) { int norm = base / (b1.a.back() + 1); bigint a = a1.abs() * norm; bigint b = b1.abs() * norm; bigint q, r; q.a.resize(a.a.size()); for(int i = a.a.size() - 1; i >= 0; i--) { r *= base; r += a.a[i]; int s1 = r.a.size() <= b.a.size() ? 0 : r.a[b.a.size()]; int s2 = r.a.size() <= b.a.size() - 1 ? 0 : r.a[b.a.size() - 1]; int d = ((long long) base * s1 + s2) / b.a.back(); r -= b * d; while(r < 0) { r += b, --d; } q.a[i] = d; } q.sign = a1.sign * b1.sign; r.sign = a1.sign; q.trim(); r.trim(); return make_pair(q, r / norm); } bigint bigint::operator/(const bigint &v) const { return divmod(*this, v).first; } bigint bigint::operator%(const bigint &v) const { return divmod(*this, v).second; } void bigint::operator/=(int v) { if(v < 0) { sign = -sign, v = -v; } for(int i = (int) a.size() - 1, rem = 0; i >= 0; --i) { long long cur = a[i] + rem * (long long) base; a[i] = (int) (cur / v); rem = (int) (cur % v); } trim(); } bigint bigint::operator/(int v) const { bigint res = *this; res /= v; return res; } int bigint::operator%(int v) const { if(v < 0) { v = -v; } int m = 0; for(int i = a.size() - 1; i >= 0; --i) { m = (a[i] + m * (long long) base) % v; } return m * sign; } void bigint::operator+=(const bigint &v) { *this = *this + v; } void bigint::operator-=(const bigint &v) { *this = *this - v; } void bigint::operator*=(const bigint &v) { *this = *this * v; } void bigint::operator/=(const bigint &v) { *this = *this / v; } bool bigint::operator<(const bigint &v) const { if(sign != v.sign) { return sign < v.sign; } if(a.size() != v.a.size()) { return a.size() * sign < v.a.size() * v.sign; } for(int i = a.size() - 1; i >= 0; i--) { if (a[i] != v.a[i]) { return a[i] * sign < v.a[i] * sign; } } return false; } bool bigint::operator>(const bigint &v) const { return v < *this; } bool bigint::operator<=(const bigint &v) const { return !(v < *this); } bool bigint::operator>=(const bigint &v) const { return !(*this < v); } bool bigint::operator==(const bigint &v) const { return !(*this < v) && !(v < *this); } bool bigint::operator!=(const bigint &v) const { return *this < v || v < *this; } void bigint::trim(void) { while(!a.empty() && !a.back()) { a.pop_back(); } if(a.empty()) { sign = 1; } } bool bigint::isZero(void) const { return a.empty() || (a.size() == 1 && !a[0]); } bigint bigint::operator-() const { bigint res = *this; res.sign = -sign; return res; } bigint bigint::abs() const { bigint res = *this; res.sign *= res.sign; return res; } long long bigint::longValue() const { long long res = 0; for(int i = a.size() - 1; i >= 0; i--) { res = res * base + a[i]; } return res * sign; } bigint gcd(const bigint &a, const bigint &b) { return b.isZero() ? a : gcd(b, a % b); } bigint lcm(const bigint &a, const bigint &b) { return a / gcd(a, b) * b; } void bigint::read(const string &s) { sign = 1; a.clear(); int pos = 0; while(pos < (int) s.size() && (s[pos] == '-' || s[pos] == '+')) { if(s[pos] == '-') { sign = -sign; } ++pos; } for(int i = s.size() - 1; i >= pos; i -= base_digits) { int x = 0; for(int j = max(pos, i - base_digits + 1); j <= i; j++) { x = x * 10 + s[j] - '0'; } a.push_back(x); } trim(); } istream& operator>>(istream &stream, bigint &v) { string s; stream >> s; v.read(s); return stream; } ostream& operator<<(ostream &stream, const bigint &v) { if(v.sign == -1) { stream << '-'; } stream << (v.a.empty() ? 0 : v.a.back()); for(int i = (int) v.a.size() - 2; i >= 0; --i) { stream << setw(base_digits) << setfill('0') << v.a[i]; } return stream; } vector bigint::convert_base(const vector &a, int old_digits, int new_digits) { vector p(max(old_digits, new_digits) + 1); p[0] = 1; for(int i = 1; i < (int) p.size(); i++) { p[i] = p[i - 1] * 10; } vector res; long long cur = 0; int cur_digits = 0; for(int i = 0; i < (int) a.size(); i++) { cur += a[i] * p[cur_digits]; cur_digits += old_digits; while(cur_digits >= new_digits) { res.push_back(int(cur % p[new_digits])); cur /= p[new_digits]; cur_digits -= new_digits; } } res.push_back((int) cur); while(!res.empty() && !res.back()) { res.pop_back(); } return res; } vector bigint::karatsubaMultiply(const vector &a, const vector &b) { int n = a.size(); vector res(n + n); if(n <= 32) { for(int i = 0; i < n; i++) { for (int j = 0; j < n; j++) { res[i + j] += a[i] * b[j]; } } return res; } int k = n >> 1; vector a1(a.begin(), a.begin() + k); vector a2(a.begin() + k, a.end()); vector b1(b.begin(), b.begin() + k); vector b2(b.begin() + k, b.end()); vector a1b1 = karatsubaMultiply(a1, b1); vector a2b2 = karatsubaMultiply(a2, b2); for(int i = 0; i < k; i++) { a2[i] += a1[i]; } for(int i = 0; i < k; i++) { b2[i] += b1[i]; } vector r = karatsubaMultiply(a2, b2); for(int i = 0; i < (int) a1b1.size(); i++) { r[i] -= a1b1[i]; } for(int i = 0; i < (int) a2b2.size(); i++) { r[i] -= a2b2[i]; } for(int i = 0; i < (int) r.size(); i++) { res[i + k] += r[i]; } for(int i = 0; i < (int) a1b1.size(); i++) { res[i] += a1b1[i]; } for(int i = 0; i < (int) a2b2.size(); i++) { res[i + n] += a2b2[i]; } return res; } bigint bigint::operator*(const bigint &v) const { vector a6 = convert_base(this->a, base_digits, 6); vector b6 = convert_base(v.a, base_digits, 6); vector a(a6.begin(), a6.end()); vector b(b6.begin(), b6.end()); while(a.size() < b.size()) { a.push_back(0); } while(b.size() < a.size()) { b.push_back(0); } while(a.size() & (a.size() - 1)) { a.push_back(0), b.push_back(0); } vector c = karatsubaMultiply(a, b); bigint res; res.sign = sign * v.sign; for(int i = 0, carry = 0; i < (int) c.size(); i++) { long long cur = c[i] + carry; res.a.push_back((int) (cur % 1000000)); carry = (int) (cur / 1000000); } res.a = convert_base(res.a, 6, base_digits); res.trim(); return res; } bigint bigint::pow(int times) const { bigint cp = *this; bigint res(1); for( ; times>0; times>>=1) { if(times & 1) { res *= cp; } cp *= cp; } return res; } const int mod = int(1e9) + 7; i64 f(bigint x) { stringstream ss; ss << x; string s = ss.str(); int n = s.size(); vector>>>> dp(n+1, vector>>>(2, vector>>(2, vector>(3, vector(8))))); dp[0][0][0][0][0] = 1; for(int i : range(n)) { for(int j : range(2)) { for(int k : range(3)) { for(int x : range(8)) { for(int d : range(j?10:s[i]-'0'+1)) { int flag = j | d < s[i] - '0'; dp[i+1][flag][d==3][(k+d)%3][(x*10+d)%8] += dp[i][j][0][k][x]; dp[i+1][flag][d==3][(k+d)%3][(x*10+d)%8] %= mod; dp[i+1][flag][1] [(k+d)%3][(x*10+d)%8] += dp[i][j][1][k][x]; dp[i+1][flag][1] [(k+d)%3][(x*10+d)%8] %= mod; } } } } } i64 res = 0; for(int j : range(2)) { for(int x : range(1, 8)) { for(int k : range(3)) { res = (res + dp[n][j][1][k][x]) % mod; } res = (res + dp[n][j][0][0][x]) % mod; } } return res % mod; } int main(void) { bigint a, b; cin >> a >> b; i64 res = f(b) - f(a-1); printf("%d\n", (res + mod) % mod); return 0; }