#include <iostream>
#include <stdio.h>
#include <fstream>
#include <assert.h>
using namespace std;

ifstream fin("arbint.in");
ofstream fout("arbint.out");

#define lungime 100001

int N, M;
int A[4 * lungime + 66];
int start, final, Val, Pos, maxim;

inline int Maxim(int a, int b)
{
    if (a > b)
        return a;
    return b;
}

void Actualizare(int nod, int st, int dr)
{
    if (st == dr)
    {
        A[nod] = Val;
        return;
    }

    int div = (st + dr) / 2;
    if (Pos <= div)
        Actualizare(2 * nod, st, div);
    else
        Actualizare(2 * nod + 1, div + 1, dr);

    A[nod] = Maxim(A[2 * nod], A[2 * nod + 1]);
}

void Interogare(int nod, int st, int dr)
{
    if (start <= st && dr <= final)
    {
        if (maxim < A[nod])
            maxim = A[nod];
        return;
    }

    int div = (st + dr) / 2;
    if (start <= div)
        Interogare(2 * nod, st, div);
    if (div < final)
        Interogare(2 * nod + 1, div + 1, dr);
}

int main()
{
    int X, A, B;
    fin >> N >> M;
    for (int i = 1; i <= N; i++)
    {
        fin >> X;
        Pos = i, Val = X;
        Actualizare(1, 1, N);
    }

    for (int i = 1; i <= M; i++)
    {
        fin >> X >> A >> B;
        if (X == 0)
        {
            maxim = -1;
            start = A, final = B;
            Interogare(1, 1, N);

            fout << maxim << endl;
        }
        else
        {
            Pos = A, Val = B;
            Actualizare(1, 1, N);
        }
    }
}