// binaris_fa.cpp : This file contains the 'main' function. Program execution begins and ends there.
//

#include <iostream>
#include<queue>
#include<cmath>
#define ll long long

using namespace std;

struct adat {
    int lat, tav, apa;
    vector<ll>sz;
};

vector<adat>x;
int n, m, i, a, b, k, l, p;

void fa(ll magassag)
{
    int j = pow(2, magassag - 1);
    for (int i = 0; i < j - 1; ++i)
    {
        x[i].sz.push_back(2 * i + 1);
        x[i].sz.push_back(2 * i + 2);
    }
    x[0].tav = magassag - 1;
    for (i = 1; i <= k - 2; ++i)
    {
        x[i].apa = 1;
        x[i].tav = x[(i - 1) / 2].tav - 1;
    }
}

void hossz(ll csp)
{
    l = x[csp * 2 + 1].apa + x[csp * 2 + 1].tav;
    p = x[csp * 2 + 2].apa + x[csp * 2 + 2].tav;
    if ((x[csp * 2 + 1].apa + x[csp * 2 + 1].tav) > (x[csp * 2 + 2].apa + x[csp * 2 + 2].tav)) x[csp].tav = x[csp * 2 + 1].apa + x[csp * 2 + 1].tav;
    else x[csp].tav = x[csp * 2 + 2].apa + x[csp * 2 + 2].tav;
    if (csp) hossz((csp - 1) / 2);
}

int main()
{
    ios_base::sync_with_stdio(false);
    cin.tie(0);
    cout.tie(0);

    cin >> n >> m;

    k = pow(2, n);
    x.resize(k);

    fa(n);

    for (i = 1; i <= m; ++i)
    {
        cin >> a >> b;
        x[a - 1].apa = b;
        if (a % 2 == 0) hossz((a - 1) / 2);
        else hossz((a - 1) / 2 - 1);

        cout << x[0].tav << endl;
    }

}

/*
3 5
2 6
4 3
6 7
5 4
2 1
*/
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