#include <algorithm>
#include <bitset>
#include <cassert>
#include <chrono>
#include <climits>
#include <cmath>
#include <complex>
#include <cstring>
#include <deque>
#include <functional>
#include <iostream>
#include <iomanip>
#include <list>
#include <map>
#include <numeric>
#include <queue>
#include <random>
#include <set>
#include <stack>
#include <unordered_map>
#include <unordered_set>
#include <vector>
#include <cstdint>
using namespace std;
typedef long long ll;
typedef vector<int> vi;
typedef pair<int,int> pii;
#define MP make_pair
#define PB push_back
#define inf 1000000007
#define rep(i,n) for(int i = 0; i < (int)(n); ++i)
#define all(x) (x).begin(),(x).end()

template<typename A, size_t N, typename T>
void Fill(A (&array)[N], const T &val){
    std::fill( (T*)array, (T*)(array+N), val );
}
 
template<class T> inline bool chmax(T &a, T b){
    if(a<b){
        a = b;
        return true;
    }
    return false;
}

template<class T> inline bool chmin(T &a, T b){
    if(a>b){
        a = b;
        return true;
    }
    return false;
}
template<typename T> class segtree {
private:
    int n,sz,h; vector<T> node, lazy;
    vector<bool> lazyFlag;
    void eval(int k) {
        if(lazyFlag[k]){
            node[k] = lazy[k];
            if(k < n) {
                lazy[k*2] = lazy[k*2+1] = lazy[k];
                lazyFlag[k*2] = lazyFlag[k*2+1] = true;
            }
            lazyFlag[k] = false;
        }
    }

public:
    segtree(const vector<T>& v) : n(1), sz((int)v.size()), h(0){
        while(n < sz) n *= 2, h++;
        node.resize(2*n, numeric_limits<T>::max());
        lazy.resize(2*n); lazyFlag.resize(2*n, false);
        for(int i = 0; i < sz; i++) node[i+n] = v[i];
        for(int i = n - 1; i >= 1; i--) node[i] = min(node[i*2], node[i*2+1]);
    }
    void range(int a, int b, T x, int k=1, int l=0, int r=-1){
        if(r < 0) r = n;
        eval(k);
        if(b <= l || r <= a) return;
        if(a <= l && r <= b){
            lazy[k] = x, lazyFlag[k] = true; eval(k);
        }else{
            range(a, b, x, 2*k, l, (l+r)/2);
            range(a, b, x, 2*k+1, (l+r)/2, r);
            node[k] = min(node[2*k], node[2*k+1]);
        }
    }
    T query(int a, int b) {
        a += n, b += n - 1;
        for(int i = h; i > 0; i--) eval(a >> i), eval(b >> i);
        b++;
        T res1 = numeric_limits<T>::max(), res2 = numeric_limits<T>::max();
        while(a < b) {
            if(a & 1) eval(a), res1 = min(res1, node[a++]);
            if(b & 1) eval(--b), res2 = min(res2, node[b]);
            a >>= 1, b >>= 1;
        }
        return min(res1, res2);
    }
    void print(){for(int i = 0; i < sz; i++) cout<<query(i,i+1)<< " ";cout<<endl;}
};

int main(){
    cin.tie();
    ios::sync_with_stdio(false);
    ll n,q;
    cin >> n >> q;
    vector<ll> a(n,n-1),b(n,n-1);
    segtree<ll> sga(a),sgb(b);
    ll res = 0;
    rep(zz,q){
        int cc,x;
        cin >> cc >> x;
        x--;
        // cerr << "test:" << zz << endl;
        if(cc==1){
            int ok = sga.query(x,x+1);
            ok--;
            // cerr << ok << endl;
            res += ok;
            if(x<sgb.query(0,1))sgb.range(0,ok+1,x);
        }else{
            int ok = sgb.query(x,x+1);
            ok--;
            // cerr << ok << endl;
            res += ok;
            if(x<sga.query(0,1))sga.range(0,ok+1,x);
        }
        // cerr << res << endl;
        // cerr << "test"<< endl;
        // sga.print();
        // sgb.print();
    }
    
    cout << (n-2)*(n-2) - res << endl;
    return 0;
}

Measured memory_bytes: 23092