#include <iostream>
#include <fstream>
#include <limits.h>
#define leftN 2*nod
#define rightN 2*nod+1
#define MAX 100000

using namespace std;

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

int arb[4*MAX+1];
int v[MAX+1];
int n,m,a,b,t;

void build(int nod, int left, int right) {
    if(left == right) {
        arb[nod] = v[left];
        //cout << arb[nod] << "[" << left << ", " << right << "]" << '\n';
        return;
    }
    int mid = (left+right)/2;
    build(leftN, left, mid);
    build(rightN, mid+1, right);
    arb[nod] = max(arb[leftN], arb[rightN]);
    //cout << arb[nod] << "[" << left << ", " << right << "]" << '\n';
}

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

void query(int nod, int left, int right, int start, int finish, int &mx) {

    //if((left < start && right < start) || (right > finish && left > finish)) // no overlap
    //    return/* INT_MAX*/;
    if(left > finish || right < start)
        return;
    if(start <= left && finish >= right) { // full overlap
        mx = max(mx, arb[nod]);
        return;
    }
    //cout << "QUERY " << left << " " << right << "   " << start << " " << finish << '\n';
        //return arb[nod];

    int mid = (left+right)/2;

    if(left <= start && mid <= finish)
        query(leftN, left, mid, start, finish, mx);
    if(mid+1 <= start && right <= finish)
        query(rightN, mid+1, right, start, finish, mx);

}

void inorder(int nod, int left, int right) {

    if(arb[nod] == 0)
        return;

    inorder(leftN, left, (left+right)/2);
    cout << arb[nod] << " [ " << left << ", " << right << " ]" << '\n';
    inorder(rightN, (left+right)/2+1, right);

}

int main() {

    in >> n >> m;

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

    build(1, 1, n);
    //inorder(1, 1, n);

    for(int i = 1; i <= m; i++) {

        in >> t >> a >> b;

        if(t == 0) {
            int mx = -1;
            query(1, 1, n, a, b, mx);
            out << mx << '\n';
        } else {
            //cout << "TEST";
            //cout << '\n';
            //update(1, 1, n, a, b);
            v[a] = b;
            build(1, 1, n);
            //inorder(1, 1, n);
        }
    }

    return 0;
}