#include <fstream>
#define MaxN 100005
#define EPS 1e-12
using namespace std;

ifstream  cin("arbint.in");
ofstream cout("arbint.out");

int AINT[3*MaxN], v[MaxN], N, M, pos, val, st, dr;

void build(int nod, int st, int dr)
{
    if (st == dr)
    {
        AINT[nod] = v[st];
    }
    else
    {
        int mid = (st + dr) / 2;
        build(2*nod, st, mid);
        build(2*nod+1, mid + 1, dr);
        AINT[nod] = max(AINT[2*nod], AINT[2*nod+1]);
    }
}

void update(int nod, int val, int pos, int st, int dr)
{
    if (st == dr)
    {
        AINT[nod] = val;
    }
    else
    {
        int mid = (st+dr)/2;
        if (pos <= mid)
        {
            update(2*nod, val, pos, st, mid);
        }
        else
        {
            update(2*nod+1, val, pos, mid + 1, dr);
        }
        AINT[nod] = max(AINT[2*nod], AINT[2*nod+1]);
    }
}

void query(int nod, int st, int dr, int q_st, int q_dr, int &ans)
{
    if (st >= q_st && dr <= q_dr) /// [st,dr] este cuprins in [q_st, q_dr]
    {
        ans = max(ans, AINT[nod]);
    }
    else
    {
        int mid = (st+dr)/2;

        if (q_st <= mid) /// intervalul de query se intersecteaza la stanga
            query(2*nod, st, mid, q_st, q_dr, ans);

        if (mid+1 <= q_dr) /// intervalul de query se intersecteaza la dreapta
            query(2*nod+1, mid+1, dr, q_st, q_dr, ans);
    }
}

int main()
{
    cin >> N >> M;

    for (int i = 1; i <= N; i++)
    {
        cin >> v[i];
    }

    build(1, 1, N);

    for (int i = 1; i <= M; i++)
    {
        int tip;
        cin >> tip;

        if (tip == 1)
        {
            int pos, val;
            cin >> pos >> val;
            update(1, val, pos, 1, N);
        }
        else
        {   val = -1;
            int a, b;
            cin >> a >> b;
            query(1, 1, N, a, b, val);
            cout << val << "\n";
        }
    }

    return 0;
}