Difference of Big Integers

Given two integers $A$ and $B$, compute the difference, $A - B$.

Input

Two integers $A$ and $B$ separated by a space character are given in a line.

Output

Print the difference in a line.

Constraints

* $-1 \times 10^{100000} \leq A, B \leq 10^{100000}$



Sample Input 1


5 8


Sample Output 1


-3


Sample Input 2


100 25


Sample Output 2


75


Sample Input 3


-1 -1


Sample Output 3


0


Sample Input 4


12 -3


Sample Output 4


15






Example

Input

5 8


Output

-3
#include <bits/stdc++.h>
using namespace std;
const int inf = 1e9;
const long long int linf = 1LL << 50;
const double EPS = 1e-10;
const int mod = 1e9 + 7;
template <class T>
bool chmax(T &a, const T &b) {
  if (a < b) {
    a = b;
    return 1;
  }
  return 0;
}
template <class T>
bool chmin(T &a, const T &b) {
  if (a > b) {
    a = b;
    return 1;
  }
  return 0;
}
template <typename T>
istream &operator>>(istream &is, vector<T> &vec) {
  for (auto &v : vec) is >> v;
  return is;
}
template <typename T>
ostream &operator<<(ostream &os, const vector<T> &vec) {
  for (int i = 0; i < vec.size(); i++) {
    os << vec[i];
    if (i + 1 != vec.size()) os << " ";
  }
  return os;
}
template <typename T>
ostream &operator<<(ostream &os, const set<T> &st) {
  for (auto itr = st.begin(); itr != st.end(); ++itr) {
    os << *itr;
    auto titr = itr;
    if (++titr != st.end()) os << " ";
  }
  return os;
}
template <typename T>
ostream &operator<<(ostream &os, const unordered_set<T> &st) {
  for (auto itr = st.begin(); itr != st.end(); ++itr) {
    os << *itr;
    auto titr = itr;
    if (++titr != st.end()) os << " ";
  }
  return os;
}
template <typename T>
ostream &operator<<(ostream &os, const multiset<T> &st) {
  for (auto itr = st.begin(); itr != st.end(); ++itr) {
    os << *itr;
    auto titr = itr;
    if (++titr != st.end()) os << " ";
  }
  return os;
}
template <typename T>
ostream &operator<<(ostream &os, const unordered_multiset<T> &st) {
  for (auto itr = st.begin(); itr != st.end(); ++itr) {
    os << *itr;
    auto titr = itr;
    if (++titr != st.end()) os << " ";
  }
  return os;
}
template <typename T1, typename T2>
ostream &operator<<(ostream &os, const pair<T1, T2> &p) {
  os << p.first << " " << p.second;
  return os;
}
template <typename T1, typename T2>
ostream &operator<<(ostream &os, const map<T1, T2> &mp) {
  for (auto itr = mp.begin(); itr != mp.end(); ++itr) {
    os << itr->first << ":" << itr->second;
    auto titr = itr;
    if (++titr != mp.end()) os << " ";
  }
  return os;
}
template <typename T1, typename T2>
ostream &operator<<(ostream &os, const unordered_map<T1, T2> &mp) {
  for (auto itr = mp.begin(); itr != mp.end(); ++itr) {
    os << itr->first << ":" << itr->second;
    auto titr = itr;
    if (++titr != mp.end()) os << " ";
  }
  return os;
}
const long long int B = 10000;
const int BW = 4;
struct BigInt {
  vector<long long int> digit;
  BigInt(long long int a = 0) {
    digit.emplace_back(a);
    normalize();
  }
  BigInt(const string &s) { from_string(s); }
  void from_string(const string &s) {
    digit.clear();
    int i;
    for (i = (int)s.size() - BW; i >= 0; i -= BW) {
      digit.emplace_back(stol(s.substr(i, BW)));
    }
    i += BW;
    if (i > 0) digit.emplace_back(stol(s.substr(0, i)));
  }
  void normalize() {
    long long int c = 0;
    for (int i = 0; i < digit.size(); i++) {
      while (digit[i] < 0) {
        if (i + 1 == digit.size()) digit.emplace_back(0);
        digit[i + 1]--;
        digit[i] += B;
      }
      long long int a = digit[i] + c;
      digit[i] = a % B;
      c = a / B;
    }
    while (c) {
      digit.emplace_back(c % B);
      c /= B;
    }
    for (int i = (int)digit.size() - 1; i >= 1; i--) {
      if (digit[i] == 0) {
        digit.pop_back();
      } else {
        break;
      }
    }
  }
  size_t size() { return digit.size(); }
  BigInt &operator=(long long int a) {
    digit.resize(1, a);
    normalize();
    return *this;
  }
  BigInt &operator=(const string &s) {
    from_string(s);
    return *this;
  }
} ZERO(0), ONE(1);
ostream &operator<<(ostream &os, const BigInt &b) {
  os << b.digit[b.digit.size() - 1];
  for (int i = (int)b.digit.size() - 2; i >= 0; i--) {
    os << setw(BW) << setfill('0') << b.digit[i];
  }
  return os;
}
istream &operator>>(istream &is, BigInt &b) {
  string s;
  is >> s;
  b.from_string(s);
  return is;
}
bool operator<(BigInt x, BigInt y) {
  if (x.digit.size() != y.digit.size()) return x.digit.size() < y.digit.size();
  for (int i = x.digit.size() - 1; i >= 0; i--) {
    if (x.digit[i] != y.digit[i]) return x.digit[i] < y.digit[i];
  }
  return false;
}
bool operator>(BigInt x, BigInt y) { return y < x; }
bool operator<=(BigInt x, BigInt y) { return !(y < x); }
bool operator>=(BigInt x, BigInt y) { return !(x < y); }
bool operator!=(BigInt x, BigInt y) { return x < y || y < x; }
bool operator==(BigInt x, BigInt y) { return !(x < y) && !(y < x); }
BigInt operator+(BigInt x, long long int a) {
  x.digit[0] += a;
  x.normalize();
  return x;
}
BigInt operator+(BigInt x, BigInt y) {
  while (x.digit.size() < y.digit.size()) x.digit.emplace_back(0);
  for (int i = 0; i < y.digit.size(); i++) x.digit[i] += y.digit[i];
  x.normalize();
  return x;
}
BigInt operator-(BigInt x, BigInt y) {
  assert(x.digit.size() >= y.digit.size());
  for (int i = 0; i < y.digit.size(); i++) x.digit[i] -= y.digit[i];
  x.normalize();
  return x;
}
BigInt operator*(BigInt x, BigInt y) {
  BigInt z;
  z.digit.assign(x.digit.size() + y.digit.size(), 0);
  for (int i = 0; i < x.digit.size(); i++) {
    for (int j = 0; j < y.digit.size(); j++) {
      z.digit[i + j] += x.digit[i] * y.digit[j];
    }
  }
  z.normalize();
  return z;
}
BigInt operator*(BigInt x, long long int a) {
  for (int i = 0; i < x.digit.size(); i++) x.digit[i] *= a;
  x.normalize();
  return x;
}
pair<BigInt, long long int> divmod(BigInt x, long long int a) {
  long long int c = 0;
  for (int i = (int)x.digit.size() - 1; i >= 0; i--) {
    long long int t = B * c + x.digit[i];
    x.digit[i] = t / a;
    c = t % a;
  }
  x.normalize();
  return make_pair(x, c);
}
BigInt operator/(BigInt x, long long int a) { return divmod(x, a).first; }
BigInt operator%(BigInt x, long long int a) { return divmod(x, a).second; }
pair<BigInt, BigInt> divmod(BigInt x, BigInt y) {
  if (x.digit.size() < y.digit.size()) return make_pair(ZERO, x);
  int F = B / (y.digit[y.digit.size() - 1] + 1);
  x = x * F;
  y = y * F;
  BigInt z;
  z.digit.assign(x.digit.size() - y.digit.size() + 1, 0);
  for (int k = (int)z.digit.size() - 1, i = (int)x.digit.size() - 1; k >= 0;
       k--, i--) {
    z.digit[k] = (i + 1 < x.digit.size() ? x.digit[i + 1] : 0) * B + x.digit[i];
    z.digit[k] /= y.digit[y.digit.size() - 1];
    BigInt t;
    t.digit.assign(k + y.digit.size(), 0);
    for (int m = 0; m < y.digit.size(); m++) {
      t.digit[k + m] = z.digit[k] * y.digit[m];
    }
    t.normalize();
    while (x < t) {
      z.digit[k] -= 1;
      for (int m = 0; m < y.digit.size(); m++) {
        t.digit[k + m] -= y.digit[m];
      }
      t.normalize();
    }
    x = x - t;
  }
  z.normalize();
  return make_pair(z, x / F);
}
BigInt operator/(BigInt x, BigInt y) { return divmod(x, y).first; }
BigInt operator%(BigInt x, BigInt y) { return divmod(x, y).second; }
BigInt &operator+=(BigInt &x, long long int a) {
  x = x + a;
  return x;
}
BigInt &operator+=(BigInt &x, BigInt y) {
  x = x + y;
  return x;
}
BigInt &operator-=(BigInt &x, BigInt y) {
  x = x - y;
  return x;
}
BigInt &operator*=(BigInt &x, BigInt y) {
  x = x * y;
  return x;
}
BigInt &operator/=(BigInt &x, BigInt y) {
  x = x / y;
  return x;
}
BigInt &operator%=(BigInt &x, BigInt y) {
  x = x % y;
  return x;
}
BigInt &operator/=(BigInt &x, long long int a) {
  x = x / a;
  return x;
}
BigInt &operator%=(BigInt &x, long long int a) {
  x = x % a;
  return x;
}
BigInt sqrt(BigInt x) {
  BigInt l = 1;
  BigInt r = x;
  while (r - l > BigInt(1)) {
    BigInt m = (r + l) / 2;
    if (m * m > x)
      r = m;
    else
      l = m;
  }
  return l;
}
struct SBigInt {
  bool neg = false;
  BigInt b = 0;
  SBigInt() {}
  SBigInt(long long int a) : b(BigInt(abs(a))) {
    if (a < 0) neg = true;
  }
  SBigInt(const string &s) {
    string t = s;
    if (t[0] == '-') {
      neg = true;
      t = t.substr(1, t.size() - 1);
    }
    b = BigInt(t);
  }
  bool operator==(const SBigInt &r) const {
    return (neg == r.neg) && (b == r.b);
  }
  bool operator!=(const SBigInt &r) const {
    return (neg != r.neg) || (b != r.b);
  }
  SBigInt operator-() {
    SBigInt res = *this;
    res.neg = !res.neg;
    return res;
  }
};
SBigInt operator+(SBigInt x, SBigInt y) {
  SBigInt res;
  if (x.neg == y.neg) {
    res.b = x.b + y.b;
    res.neg = x.neg;
  } else {
    if (x.b > y.b) {
      res.b = x.b - y.b;
      res.neg = x.neg;
    } else {
      res.b = y.b - x.b;
      res.neg = y.neg;
    }
  }
  return res;
}
SBigInt operator-(SBigInt x, SBigInt y) { return x + (-y); }
SBigInt operator*(SBigInt x, SBigInt y) {
  SBigInt res;
  res.neg = !(x.neg == y.neg);
  res.b = x.b * y.b;
  return res;
}
SBigInt operator/(SBigInt x, SBigInt y) {
  SBigInt res;
  res.neg = !(x.neg == y.neg);
  res.b = x.b / y.b;
  return res;
}
ostream &operator<<(ostream &os, const SBigInt &b) {
  if (b.neg) os << "-";
  os << b.b;
  return os;
}
int main(int argc, char const *argv[]) {
  ios_base::sync_with_stdio(false);
  cin.tie(0);
  string a, b;
  cin >> a >> b;
  SBigInt A(a), B(b);
  cout << A - B << endl;
  return 0;
}
