#include <iostream>
#include <fstream>
#include <cmath>
#define nmax 100001

using namespace std;

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

int n, cnt;
int arb[nmax * 4 + 66];
int start, finish, poz, val, maxim;

void update(int nod, int left, int right){
    if(left == right){
        arb[nod] = val;
        return;
    }
    int mid = (left + right) / 2;
    if(poz <= mid){
        update(nod * 2, left, mid);
    }
    else{
        update(nod * 2 + 1, mid + 1, right);
    }
    arb[nod] = max(arb[2 * nod + 1], arb[2 * nod]);
}

void query(int nod, int left, int right){
    if(start <= left && right <= finish){
        if(maxim < arb[nod]){
            maxim = arb[nod];
        }
        return;
    }
    int mid = (left + right) / 2;
    if(start <= mid){
        query(nod * 2, left, mid);
    }
    if(mid < finish){
        query(nod * 2 + 1, mid + 1, right);
    }
}

int main()
{
    in >> n >> cnt;
    for(int i = 1;i <= n;i++){
        int x;
        in >> x;
        val = x;
        poz = i;
        update(1, 1, n);
    }
    for(int i = 1; i <= cnt;i++){
        int task, a, b;
        in >> task >> a >> b;
        if(task == 1){
            poz = a;
            val = b;
            update(1, 1, n);
        }
        else{
            maxim = -1;
            start = a;
            finish = b;
            query(1, 1, n);
            out << maxim << '\n';
        }
    }
    return 0;
}