//g++ t.cpp -o t && t < p.txt
//d>p.txt&&t<p.txt&&t2<p.txt

#ifndef ATCODER_INTERNAL_BITOP_HPP
#define ATCODER_INTERNAL_BITOP_HPP 1

#ifdef _MSC_VER
#include <intrin.h>
#endif

namespace atcoder {

namespace internal {

// @param n `0 <= n`
// @return minimum non-negative `x` s.t. `n <= 2**x`
int ceil_pow2(int n) {
    int x = 0;
    while ((1U << x) < (unsigned int)(n)) x++;
    return x;
}

// @param n `1 <= n`
// @return minimum non-negative `x` s.t. `(n & (1 << x)) != 0`
int bsf(unsigned int n) {
#ifdef _MSC_VER
    unsigned long index;
    _BitScanForward(&index, n);
    return index;
#else
    return __builtin_ctz(n);
#endif
}

}  // namespace internal

}  // namespace atcoder

#endif  // ATCODER_INTERNAL_BITOP_HPP

#ifndef ATCODER_LAZYSEGTREE_HPP
#define ATCODER_LAZYSEGTREE_HPP 1

#include <algorithm>
#include <cassert>
#include <iostream>
#include <vector>
namespace atcoder {

template <class S,
          S (*op)(S, S),
          S (*e)(),
          class F,
          S (*mapping)(F, S),
          F (*composition)(F, F),
          F (*id)()>
struct lazy_segtree {
  public:
    lazy_segtree() : lazy_segtree(0) {}
    lazy_segtree(int n) : lazy_segtree(std::vector<S>(n, e())) {}
    lazy_segtree(const std::vector<S>& v) : _n(int(v.size())) {
        log = internal::ceil_pow2(_n);
        size = 1 << log;
        d = std::vector<S>(2 * size, e());
        lz = std::vector<F>(size, id());
        for (int i = 0; i < _n; i++) d[size + i] = v[i];
        for (int i = size - 1; i >= 1; i--) {
            update(i);
        }
    }

    void set(int p, S x) {
        assert(0 <= p && p < _n);
        p += size;
        for (int i = log; i >= 1; i--) push(p >> i);
        d[p] = x;
        for (int i = 1; i <= log; i++) update(p >> i);
    }

    S get(int p) {
        assert(0 <= p && p < _n);
        p += size;
        for (int i = log; i >= 1; i--) push(p >> i);
        return d[p];
    }

    S prod(int l, int r) {
        assert(0 <= l && l <= r && r <= _n);
        if (l == r) return e();

        l += size;
        r += size;

        for (int i = log; i >= 1; i--) {
            if (((l >> i) << i) != l) push(l >> i);
            if (((r >> i) << i) != r) push(r >> i);
        }

        S sml = e(), smr = e();
        while (l < r) {
            if (l & 1) sml = op(sml, d[l++]);
            if (r & 1) smr = op(d[--r], smr);
            l >>= 1;
            r >>= 1;
        }

        return op(sml, smr);
    }

    S all_prod() { return d[1]; }

    void apply(int p, F f) {
        assert(0 <= p && p < _n);
        p += size;
        for (int i = log; i >= 1; i--) push(p >> i);
        d[p] = mapping(f, d[p]);
        for (int i = 1; i <= log; i++) update(p >> i);
    }
    void apply(int l, int r, F f) {
        assert(0 <= l && l <= r && r <= _n);
        if (l == r) return;

        l += size;
        r += size;

        for (int i = log; i >= 1; i--) {
            if (((l >> i) << i) != l) push(l >> i);
            if (((r >> i) << i) != r) push((r - 1) >> i);
        }

        {
            int l2 = l, r2 = r;
            while (l < r) {
                if (l & 1) all_apply(l++, f);
                if (r & 1) all_apply(--r, f);
                l >>= 1;
                r >>= 1;
            }
            l = l2;
            r = r2;
        }

        for (int i = 1; i <= log; i++) {
            if (((l >> i) << i) != l) update(l >> i);
            if (((r >> i) << i) != r) update((r - 1) >> i);
        }
    }

    template <bool (*g)(S)> int max_right(int l) {
        return max_right(l, [](S x) { return g(x); });
    }
    template <class G> int max_right(int l, G g) {
        assert(0 <= l && l <= _n);
        assert(g(e()));
        if (l == _n) return _n;
        l += size;
        for (int i = log; i >= 1; i--) push(l >> i);
        S sm = e();
        do {
            while (l % 2 == 0) l >>= 1;
            if (!g(op(sm, d[l]))) {
                while (l < size) {
                    push(l);
                    l = (2 * l);
                    if (g(op(sm, d[l]))) {
                        sm = op(sm, d[l]);
                        l++;
                    }
                }
                return l - size;
            }
            sm = op(sm, d[l]);
            l++;
        } while ((l & -l) != l);
        return _n;
    }

    template <bool (*g)(S)> int min_left(int r) {
        return min_left(r, [](S x) { return g(x); });
    }
    template <class G> int min_left(int r, G g) {
        assert(0 <= r && r <= _n);
        assert(g(e()));
        if (r == 0) return 0;
        r += size;
        for (int i = log; i >= 1; i--) push((r - 1) >> i);
        S sm = e();
        do {
            r--;
            while (r > 1 && (r % 2)) r >>= 1;
            if (!g(op(d[r], sm))) {
                while (r < size) {
                    push(r);
                    r = (2 * r + 1);
                    if (g(op(d[r], sm))) {
                        sm = op(d[r], sm);
                        r--;
                    }
                }
                return r + 1 - size;
            }
            sm = op(d[r], sm);
        } while ((r & -r) != r);
        return 0;
    }

  private:
    int _n, size, log;
    std::vector<S> d;
    std::vector<F> lz;

    void update(int k) { d[k] = op(d[2 * k], d[2 * k + 1]); }
    void all_apply(int k, F f) {
        d[k] = mapping(f, d[k]);
        if (k < size) lz[k] = composition(f, lz[k]);
    }
    void push(int k) {
        all_apply(2 * k, lz[k]);
        all_apply(2 * k + 1, lz[k]);
        lz[k] = id();
    }
};

}  // namespace atcoder

#endif  // ATCODER_LAZYSEGTREE_HPP


#include <iostream> // プログラムの耳と口
#include <vector> // 超有能配列秘書
#include <algorithm> // みんな大好きソートと二分探索
#include <queue> // きゅーちゃん、だいすき
#include <string> // to_string
#include <functional> // 関数を変数に入れる子
#include <set> // 値の取得・挿入・削除を高速に
#include <map> // setの妹 これまた優秀
#include <random> // 乱択さん
#include <ctime>
#include <bitset>

#define DB cerr<<"D"<<endl
using namespace atcoder;
using namespace std; using ll=long long; using ld=long double; const int INF=1e9; const ll LINF=1e18; const double dINF = 1e18; const ld ldINF = 1e18; const double EPS = 1e-6;
template<typename T, typename U, typename O> void caut(T a, U b, O c){cout<<"("<<a<<","<<b<<","<<c<<") ";} template<typename T, typename U> void caut(T a, U b){cout<<"("<<a<<","<<b<<") ";} template<typename T> void caut(T a){cout<<"("<<a<<") ";};
using P=pair<ll,ll>;
const ll M = 998244353;
ll mod_pow(ll x, ll a) { ll an = 1; while(a > 0) { if (a&1) an = an * x % M; x = x * x % M; a >>= 1;} return an;}
ll mod_pow(ll x, ll a, ll m) { ll an = 1; while(a > 0) { if (a&1) an = an * x % m; x = x * x % m; a >>= 1;} return an;}
void add(ll& x, ll y) {x+=y; x%=M;}; void mul(ll& x, ll y) {x*=y; x%=M;}; template<typename T, typename U> void chmax(T& x, U y) {if (x<y) x=y;}; template<typename T, typename U> void chmin(T& x, U y) {if (x>y) x=y;}
bool vaild(int x, int y, int hh, int ww){return 0<=x&&x<hh&&0<=y&&y<ww;}
int keta(ll a) {int res=0; while(a>0) res+=a%10, a/=10; return res;}
const int up[]={1,-1,0,0}, lf[]={0,0,1,-1};
ll gcd(ll a, ll b) {if (b==0) return a; else return gcd(b, a%b);}

int op(int a, int b){return min(a,b);}
int mapping(int a, int b){return min(a,b);}
int composition(int a, int b){return min(a,b);}
int n0;
int e(){return n0-2;}
int id(){return n0-2;}

int main() {
  ll n,q; cin>>n>>q; n0=n;
  ll an = (n-2) * (n-2);
  lazy_segtree<int, op, e, int, mapping, composition, id> s1(n);
  lazy_segtree<int, op, e, int, mapping, composition, id> s2(n);
  s1.set(0,0); s1.set(n-1,0); s2.set(0,0); s2.set(n-1,0);

  for(int _=0;_<q;_++) {
    int __; cin>>__;
    int p; cin>>p; p--;
    if (__ == 1) {
      int gt = s1.get(p);
      an -= gt; s1.set(p, 0);
      s2.apply(1, gt+1, p-1);
    } else {
      int gt = s2.get(p);
      an -= gt; s2.set(p, 0);
      s1.apply(1, gt+1, p-1);
    }
    /*
    for(int j=0;j<n;j++) {
      cout<<s1.get(j)<<" ";
    } cout<<endl;
    for(int j=0;j<n;j++) {
      cout<<s2.get(j)<<" ";
    } cout<<endl;*/
  }
  cout<<an<<endl;
}
// ・配列の大きさok？　・priority_queueはgreater？　・debug消した？
// ・落ち着いて。提出まで4分待ってね……WJ……1/10……2/10……

// Thank you for making problems and running the contest


Measured memory_bytes: 10168