#include <bits/stdc++.h>
using namespace std;
using vint = vector<long long>;
using vvint = vector<vint>;
using pint = pair<long long, long long>;
using vpint = vector<pint>;
template <typename T>
using priority_queue_rev = priority_queue<T, vector<T>, greater<T>>;
constexpr double PI = 3.1415926535897932384626433832795028;
constexpr long long DY[9] = {0, 1, 0, -1, 1, 1, -1, -1, 0};
constexpr long long DX[9] = {1, 0, -1, 0, 1, -1, -1, 1, 0};
long long gcd(long long a, long long b) {
  while (b) {
    swap(a %= b, b);
  }
  return a;
}
long long lcm(long long a, long long b) { return a / gcd(a, b) * b; }
long long sgn(long long x) { return (x > 0) - (x < 0); }
template <typename T>
void fin(T mes) {
  cout << mes << endl;
  exit(0);
}
template <typename T, typename U>
bool chmax(T &a, const U &b) {
  if (a < b) {
    a = b;
    return true;
  }
  return false;
}
template <typename T, typename U>
bool chmin(T &a, const U &b) {
  if (b < a) {
    a = b;
    return true;
  }
  return false;
}
template <typename T, typename U>
ostream &operator<<(ostream &os, const pair<T, U> &rhs) {
  os << "(" << rhs.first << ", " << rhs.second << ")";
  return os;
}
template <typename T>
ostream &operator<<(ostream &os, const vector<T> &rhs) {
  os << "{";
  for (auto itr = rhs.begin(); itr != rhs.end(); itr++) {
    os << *itr << (next(itr) != rhs.end() ? ", " : "");
  }
  os << "}";
  return os;
}
template <typename T>
ostream &operator<<(ostream &os, const deque<T> &rhs) {
  os << "{";
  for (auto itr = rhs.begin(); itr != rhs.end(); itr++) {
    os << *itr << (next(itr) != rhs.end() ? ", " : "");
  }
  os << "}";
  return os;
}
template <typename T>
ostream &operator<<(ostream &os, const set<T> &rhs) {
  os << "{";
  for (auto itr = rhs.begin(); itr != rhs.end(); itr++) {
    os << *itr << (next(itr) != rhs.end() ? ", " : "");
  }
  os << "}";
  return os;
}
template <typename T, typename U>
ostream &operator<<(ostream &os, const map<T, U> &rhs) {
  os << "{";
  for (auto itr = rhs.begin(); itr != rhs.end(); itr++) {
    os << *itr << (next(itr) != rhs.end() ? ", " : "");
  }
  os << "}";
  return os;
}
struct setup {
  static constexpr long long PREC = 20;
  setup() {
    cout << fixed << setprecision(PREC);
    cerr << fixed << setprecision(PREC);
  };
} setup;
long long N, M;
long long L[220000], R[220000];
pint LR[220000];
signed main() {
  cin >> N >> M;
  for (long long i = 0; i < (long long)(N); i++) {
    cin >> L[i] >> R[i];
    LR[i] = {L[i], M + 1 - R[i]};
  }
  sort(LR, LR + N);
  priority_queue<long long> pql;
  vint v;
  for (long long i = 0; i < (long long)(N); i++) {
    pql.push(LR[i].second);
    if (pql.size() > LR[i].first) {
      v.push_back(pql.top()), pql.pop();
    }
  }
  sort((v).begin(), (v).end());
  long long s = 0;
  for (long long i = 0; i < (long long)(v.size()); i++) {
    if (s < v[i]) {
      s++;
    }
  }
  long long ans = N - (pql.size() + s);
  chmax(ans, 0);
  cout << ans << endl;
}
