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

// macros
#define pb emplace_back
#define mk make_pair
#define FOR(i, a, b) for(int i=(a);i<(b);++i)
#define rep(i, n) FOR(i, 0, n)
#define rrep(i, n) for(int i=((int)(n)-1);i>=0;i--)
#define irep(itr, st) for(auto itr = (st).begin(); itr != (st).end(); ++itr)
#define irrep(itr, st) for(auto itr = (st).rbegin(); itr != (st).rend(); ++itr)
#define all(x) (x).begin(),(x).end()
#define sz(x) ((int)(x).size())
#define UNIQUE(v) v.erase(unique(v.begin(), v.end()), v.end())
#define bit(n) (1LL<<(n))
// functions
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;}
//  types
using ll = long long int;
using P = pair<int, int>;
// constants
const int inf = 1e9;
const ll linf = 1LL << 50;
const double EPS = 1e-10;
const int mod = 1000000007;
const int dx[4] = {-1, 0, 1, 0};
const int dy[4] = {0, -1, 0, 1};
// io
struct fast_io{
  fast_io(){ios_base::sync_with_stdio(false); cin.tie(0); cout << fixed << setprecision(20);}
} fast_io_;

struct Bigint{
  const ll base = 100000000;
  const int b = 8;
  int sign = 1;
  vector<ll> dg;
  Bigint(){}
  Bigint(ll x){
    if(x < 0){
      sign = -1;
      x *= -1;
    }
    while(x){
      dg.push_back(x % base);
      x /= base;
    }
  }
  Bigint(const string &s){
    int e = 0;
    if(s[0] == '-'){
      sign = -1;
      e++;
    }
    for(int i = int(s.size()) - 1; i >= e; i-=b){
      int B = (i - b + 1 >= e ? b: i + 1 - e);
      ll x = stoll(s.substr(max(e, i - b + 1), B));
      dg.push_back(x);
    }
  }
  Bigint& operator=(const string &s){
    *this = Bigint(s);
    return *this;
  }
  Bigint& operator=(const Bigint &x){
    sign = x.sign;
    dg = x.dg;
    return *this;
  }
  Bigint& operator=(ll x){
    return (*this = Bigint(x));
  }
  Bigint operator-() const{
    Bigint res = *this;
    res.sign *= -1;
    return res;
  }
  Bigint operator+(const Bigint &x) const{
    if(sign == x.sign){
      Bigint res;
      res.sign = sign;
      res.dg.resize(max(dg.size(), x.dg.size()));
      ll carry = 0;
      for(int i = 0; i < max(dg.size(), x.dg.size()); i++){
        ll tmp = carry;
        if(i < dg.size())tmp += dg[i];
        if(i < x.dg.size())tmp += x.dg[i];
        res.dg[i] = (tmp % base);
        carry = tmp / base;
      }
      while(carry){
        res.dg.push_back(carry % base);
        carry /= base;
      }
      return res;
    }else{
      return (*this - (- x));
    }
  }
  void trim(){
    while(!dg.empty() && dg.back() == 0)dg.pop_back();
    if(dg.empty())sign = 1;
  }
  Bigint abs() const{
    Bigint res = *this;
    res.sign = 1;
    return res;
  }
  Bigint operator-(const Bigint &x) const{
    if(sign == x.sign){
      if(abs() >= x.abs()){
        Bigint res = *this;
        ll carry = 0;
        for(int i = 0; i < x.dg.size(); i++){
          res.dg[i] -= carry + x.dg[i];
          if(res.dg[i] < 0){
            res.dg[i] += base;
            carry = 1;
          }else{
            carry = 0;
          }
        }
        if(carry > 0){
          for(int i = x.dg.size(); i < res.dg.size() && carry > 0; i++){
            res.dg[i] -= carry;
            if(res.dg[i] < 0){
              res.dg[i] += base;
              carry = 1;
            }else{
              carry = 0;
            }
          }
        }
        res.trim();
        return res;
      }else{
        return - (x - *this);
      }
    }else{
      return (*this + (- x));
    }
  }
  bool operator<(const Bigint &x) const{
    if(sign != x.sign)return sign < x.sign;
    if(dg.size() != x.dg.size())return int(dg.size()) * sign < int(x.dg.size()) * x.sign;
    for(int i = int(dg.size()) - 1; i >= 0; i--){
      if(dg[i] != x.dg[i])return dg[i] * sign < x.dg[i] * x.sign;
    }
    return false;
  }
  bool operator>(const Bigint &x) const{
    return x < *this;
  }
  bool operator<=(const Bigint &x) const{
    return !(*this > x);
  }
  bool operator>=(const Bigint &x) const{
    return !(*this < x);
  }
  bool operator==(const Bigint &x) const{
    return !(*this < x) && !(x < *this);
  }
  bool operator!=(const Bigint &x) const{
    return (*this < x) || (x < *this);
  }
  friend istream& operator>>(istream &is, Bigint &x){
    string s;
    is >> s;
    x = s;
    return is;
  }
  friend ostream& operator<<(ostream& os, const Bigint &x){
    if(x.sign < 0)os << '-';
    if(x.dg.empty())os << 0;
    else{
      os << x.dg.back();
      for(int i = int(x.dg.size()) - 2; i >= 0; i--){
        os << setw(x.b) << setfill('0') << x.dg[i];
      }
    }
    return os;
  }
};

int main(int argc, char const* argv[])
{
  Bigint a, b;
  cin >> a >> b;
  cout << a - b << endl;
  return 0;
}



Measured memory_bytes: 3524