#include <algorithm>
#include <complex>
#include <cstdlib>
#include <ctime>
#include <time.h>
#include <iomanip>
#include <iostream>
#include <map>
#include <math.h>
#include <queue>
#include <random>
#include <set>
#include <sstream>
#include <stack>
#include <string>
#include <vector>
#include <numeric>
#include <limits>
#include <type_traits>
#include <locale>
#include <omp.h>

using namespace std;
#define SAY_YES cout << "YES" << endl;
#define SAY_Yes cout << "Yes" << endl;
#define SAY_NO cout << "NO" << endl;
#define SAY_No cout << "No" << endl;
#define IFYES(TRUE_OR_FALSE)   \
    if (TRUE_OR_FALSE)         \
    {                          \
        cout << "YES" << endl; \
    }                          \
    else                       \
    {                          \
        cout << "NO" << endl;  \
    }
#define IFYes(TRUE_OR_FALSE)   \
    if (TRUE_OR_FALSE)         \
    {                          \
        cout << "Yes" << endl; \
    }                          \
    else                       \
    {                          \
        cout << "No" << endl;  \
    }
#define IFyes(TRUE_OR_FALSE)   \
    if (TRUE_OR_FALSE)         \
    {                          \
        cout << "yes" << endl; \
    }                          \
    else                       \
    {                          \
        cout << "no" << endl;  \
    }
#define DEBUG_OUTPUT_ARRAY(XXX, ONE)                            \
    for (int i = 0; i < (ONE); i++)                             \
    {                                                           \
        cout << "DEBUG: i = " << i << " -> " << XXX[i] << endl; \
    }
#define DEBUG_OUTPUT_ARRAY2(XXX, ONE, TWO)                             \
    for (int i = 0; i < (ONE); i++)                                    \
    {                                                                  \
        cout << "<<< i = " << i << " >>>" << endl;                     \
        for (int j = 0; j < (TWO); j++)                                \
        {                                                              \
            cout << "DEBUG: j = " << j << " -> " << XXX[i][j] << endl; \
        }                                                              \
    }
#define DEBUG_OUTPUT_ARRAY2_BOX(XXX, ONE, TWO) \
    for (int i = 0; i < (ONE); i++)            \
    {                                          \
        cout << i << "  ";                     \
        for (int j = 0; j < (TWO); j++)        \
        {                                      \
            cout << XXX[i][j] << " ";          \
        }                                      \
        cout << endl;                          \
    }

typedef pair<long long int, long long int> pll;
typedef pair<long long int, pll> lpll;

const long long int mod = 998244353;
const long long int INF = 1e18;
const long double PI=3.14159265358979323; 
//const long long int pl=1000000;

long long int N,Q,X,sum=0,res=0,type[200200],x[200063],nokori;
pll memo[500005]={};
string S;
long long int H[200020],W[200020],minH,minW,HoldH,HoldW;
int main(){
    cout << fixed << setprecision(18);
    cin>>N>>Q;
    for(long long int i = 2; i <= N-1; i++){
        H[i]=INF;
        W[i]=INF;
    }
    minW=N;
    minH=N;
    res=(N-2)*(N-2);
    for(long long int i = 0; i < Q; i++){
        cin>>type[i]>>x[i];
        //cout<<minH<<" "<<minW<<" "<<res<<endl;
        if(type[i]==1){
            if(minW>x[i]){
                for(long long int j = x[i]; j < minW; j++){
                    W[j]=(minH-2);
                }
                minW=x[i];
                res-=(minH-2);

            }else{
                res-=W[x[i]];
            }

        }else{
            if(minH>x[i]){
                for(long long int j = x[i]; j < minH; j++){
                    H[j]=(minW-2);
                }
                minH=x[i];
                res-=(minW-2);

            }else{
                res-=H[x[i]];
            }
        }
    }
    cout<<res<<endl;
}



Measured memory_bytes: 9868