#include <bits/stdc++.h>

using namespace std;

using int64 = long long;
// const int mod = 1e9 + 7;
const int mod = 998244353;

const int64 infll = (1LL << 62) - 1;
const int inf = (1 << 30) - 1;

struct IoSetup {
  IoSetup() {
    cin.tie(nullptr);
    ios::sync_with_stdio(false);
    cout << fixed << setprecision(10);
    cerr << fixed << setprecision(10);
  }
} iosetup;


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 >
istream &operator>>(istream &is, pair< T1, T2 > &p) {
  is >> p.first >> p.second;
  return is;
}

template< typename T >
ostream &operator<<(ostream &os, const vector< T > &v) {
  for(int i = 0; i < (int) v.size(); i++) {
    os << v[i] << (i + 1 != v.size() ? " " : "");
  }
  return os;
}

template< typename T >
istream &operator>>(istream &is, vector< T > &v) {
  for(T &in : v) is >> in;
  return is;
}

template< typename T1, typename T2 >
inline bool chmax(T1 &a, T2 b) { return a < b && (a = b, true); }

template< typename T1, typename T2 >
inline bool chmin(T1 &a, T2 b) { return a > b && (a = b, true); }

template< typename T = int64 >
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 V >
typename enable_if< is_class< T >::value == 0 >::type fill_v(T &t, const V &v) {
  t = v;
}

template< typename T, typename V >
typename enable_if< is_class< T >::value != 0 >::type fill_v(T &t, const V &v) {
  for(auto &e : t) fill_v(e, v);
}

template< typename F >
struct FixPoint : F {
  FixPoint(F &&f) : F(forward< F >(f)) {}

  template< typename... Args >
  decltype(auto) operator()(Args &&... args) const {
    return F::operator()(*this, forward< Args >(args)...);
  }
};

template< typename F >
inline decltype(auto) MFP(F &&f) {
  return FixPoint< F >{forward< F >(f)};
}

/**
 * @brief Dual-Segment-Tree(双対セグメント木)
 * @docs docs/dual-segment-tree.md
 */
template< typename OperatorMonoid, typename H >
struct DualSegmentTree {
  int sz, height;
  vector< OperatorMonoid > lazy;
  const H h;
  const OperatorMonoid OM0;

  DualSegmentTree(int n, const H h, const OperatorMonoid &OM0) : h(h), OM0(OM0) {
    sz = 1;
    height = 0;
    while(sz < n) sz <<= 1, height++;
    lazy.assign(2 * sz, OM0);
  }

  inline void propagate(int k) {
    if(lazy[k] != OM0) {
      lazy[2 * k + 0] = h(lazy[2 * k + 0], lazy[k]);
      lazy[2 * k + 1] = h(lazy[2 * k + 1], lazy[k]);
      lazy[k] = OM0;
    }
  }

  inline void thrust(int k) {
    for(int i = height; i > 0; i--) propagate(k >> i);
  }

  void update(int a, int b, const OperatorMonoid &x) {
    thrust(a += sz);
    thrust(b += sz - 1);
    for(int l = a, r = b + 1; l < r; l >>= 1, r >>= 1) {
      if(l & 1) lazy[l] = h(lazy[l], x), ++l;
      if(r & 1) --r, lazy[r] = h(lazy[r], x);
    }
  }

  OperatorMonoid operator[](int k) {
    thrust(k += sz);
    return lazy[k];
  }
};

template< typename OperatorMonoid, typename H >
DualSegmentTree< OperatorMonoid, H > get_dual_segment_tree(int N, const H &h, const OperatorMonoid &OM0) {
  return {N, h, OM0};
}

int main() {
  int N, Q;
  cin >> N >> Q;
  int last_y = N, last_x = N;
  int64 ret = 0;

  auto f = [](int a, int b) { return min(a, b); };
  auto latte = get_dual_segment_tree(N, f, N);
  auto malta = get_dual_segment_tree(N, f, N);

  for(int i = 0; i < Q; i++) {
    int t, x;
    cin >> t >> x;
    if(t == 1) {
      // [1, last_y) をひっくり返す
      ret += latte[x] - 1;
      malta.update(0, latte[x], x);
    } else {
      ret += malta[x] - 1;
      latte.update(0, malta[x], x);
    }
  }
  cout << 1LL * (N - 2) * (N - 2) - ret + Q << "\n";
}

Measured memory_bytes: 7396