#include <iostream>
#include <iomanip>
#include <algorithm>
#include <bitset>
#include <set>
#include <unordered_set>
#include <map>
#include <unordered_map>
#include <cmath>
#include <time.h>
#include <random>
#include <string>
#include <cassert>
#include <vector>
#include <ostream>
#include <istream>
#include <stack>
#include <deque>
#include <queue>
#include <functional>
#include <chrono>
#include <stack>

using namespace std;

#define int long long
#define pb push_back
#define all(a) (a).begin(), (a).end()
#define pii pair<int, int>
#define ld long double

ostream& operator<< (ostream &out, const vector<int> &b) {
    for (auto k : b) out << k << " ";
    return out;
}

istream& operator>> (istream& in, pii& b) {
    in >> b.first >> b.second;
    return in;
}

ostream& operator<< (ostream& out, const pii& b) {
    out << "{" << b.first << ", " << b.second << "}";
    return out;
}

template <typename T1, typename T2> inline bool chkmin(T1 &x, const T2 &y) {if (x > y) {x = y; return 1;} return 0;}
template <typename T1, typename T2> inline bool chkmax(T1 &x, const T2 &y) {if (x < y) {x = y; return 1;} return 0;}


#ifdef LOCAL
    #define dbg(x) cout << #x << " : " << (x) << "\n";
    const int INF = 1e18;
    // const int mod = 2600000069;
    // const int p = 10;
#else
    #define dbg(x) 57
    const int INF = 1e18;
    // const int mod = 2600000069;
    // const int p = 179;
#endif

const ld PI = acos(-1);

#define time clock() / (double) CLOCKS_PER_SEC

// #pragma GCC optimize("Ofast,no-stack-protector")
// #pragma GCC target("sse,sse2,sse3,sse3,sse4")
// #pragma GCC optimize("unroll-loops")
// #pragma GCC optimize("fast-math")
// #pragma GCC target("avx2")  
// #pragma GCC optimize("section-anchors")
// #pragma GCC optimize("profile-values,profile-reorder-functions,tracer")
// #pragma GCC optimize("vpt")
// #pragma GCC optimize("rename-registers")
// #pragma GCC optimize("move-loop-invariants")
// #pragma GCC optimize("unswitch-loops")
// #pragma GCC optimize("function-sections")
// #pragma GCC optimize("data-sections")

mt19937 gen(chrono::high_resolution_clock::now().time_since_epoch().count());

const int MAXN = 2e5 + 10;

int t[2][8 * MAXN], mod[2][8 * MAXN];

void push(int ind, int v) {
    if (mod[ind][v] == -1) {
        return;
    }
    t[ind][v] = mod[ind][v];
    mod[ind][2 * v + 1] = mod[ind][2 * v + 2] = mod[ind][v];
    mod[ind][v] = -1;
    return;
}

void build(int ind, int v, int l, int r, int val) {
    mod[ind][v] = -1;
    if (l + 1 == r) {
        t[ind][v] = val;
        return;
    }
    int m = (l + r) / 2;
    build(ind, 2 * v + 1, l, m, val);
    build(ind, 2 * v + 2, m, r, val);
    t[ind][v] = min(t[ind][2 * v + 1], t[ind][2 * v + 2]);
}

void update(int ind, int v, int l, int r, int askl, int askr, int val) {
    push(ind, v);
    if (l >= askr || r <= askl) return;
    if (l >= askl && r <= askr) {
        mod[ind][v] = val;
        push(ind, v);
        return;
    }
    int m = (l + r) / 2;
    update(ind, 2 * v + 1, l, m, askl, askr, val);
    update(ind, 2 * v + 2, m, r, askl, askr, val);
    t[ind][v] = min(t[ind][2 * v + 1], t[ind][2 * v + 2]);
}

int ask(int ind, int v, int l, int r, int pos) {
    push(ind, v);
    if (l + 1 == r) {
        return t[ind][v];
    }
    int m = (l + r) / 2;
    if (pos < m) return ask(ind, 2 * v + 1, l, m, pos);
    else return ask(ind, 2 * v + 2, m, r, pos);
}

int n, q;

signed main() {
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    cout.tie(0);
    cin >> n >> q;
    build(0, 0, 0, n, n - 1);
    build(1, 0, 0, n, n - 1);
    int ans = (n - 2) * (n - 2);
    vector<int> mn(2, n - 1);
    for (int i = 0; i < q; i++) {
        int t, x;
        cin >> t >> x;
        x--;
        t--;
        int len = ask(t, 0, 0, n, x) - 1;
        ans -= len;
        if (chkmin(mn[t], x)) {
            update(!t, 0, 0, n, 0, len + 1, x);
        }
    }
    cout << ans << "\n";
}
/*

*/

Measured memory_bytes: 27368