#include <bits/stdc++.h>
using namespace std;

#define pb push_back
#define dbg(x) cout << #x <<": " << x << "\n";
#define sz(x) ((int)x.size())

using ll = long long;

const string fn = "arbint";
ifstream fin(fn + ".in");
ofstream fout(fn + ".out");

int n, m;
int a[4 * 100005];
void build(int nod, int st, int dr){
    if(st == dr)
        fin >> a[nod];
    else{
        int mid = (st + dr) >> 1;
        build(nod << 1, st, mid);
        build(nod << 1 | 1, mid + 1, dr);
        a[nod] = max(a[nod << 1], a[nod << 1 | 1]);
    }
}

void upd(int nod, int st, int dr, int p, int x){
    if(st == dr){
        a[nod] = x;
    }
    else{
        int mid = (st + dr) >> 1;
        if(p <= mid)
            upd(nod << 1, st, mid, p, x);
        else
            upd(nod << 1 | 1, mid + 1, dr, p, x);
        a[nod] = max(a[nod << 1 | 1], a[nod << 1]);
    }
        
}

int qry(int nod, int st, int dr, int x, int y){

    if(st > dr || st > y || dr < x)
        return -1;
    if(st >= x && dr <= y)
        return a[nod];
    int mid = (st + dr) >> 1;
    int q1 = qry(nod << 1, st, mid, x, y);
    int q2 = qry(nod << 1 | 1, mid + 1, dr, x, y);
    return max(q1, q2);
}


int main(){

    fin >> n >> m;
    build(1, 1, n);
    while(m--){
        int op, x, y;
        fin >> op >> x >> y;
        if(op == 0)
            fout << qry(1, 1, n, x, y) << "\n";
        else
            upd(1, 1, n, x, y);
    }

    return 0;
}