#include <bits/stdc++.h>

#define NM 400002

using namespace std;

int n, m, ai[NM];

void upd (int st, int dr, int node, int pos, int val)
{
    if(st == dr)
    {
        ai[node] = val;
        return;
    }
    int mid = (st + dr) / 2;
    if(pos <= mid)
        upd(st, mid, node * 2, pos, val);
    else
        upd(mid + 1, dr, node * 2 + 1, pos, val);
    ai[node] = max(ai[node * 2], ai[node * 2 + 1]);
}

int qry (int st, int dr, int node, int qa, int qb)
{
    int r1 = 0, r2 = 0;
    if(qa <= st && qb >= dr)
        return ai[node];
    int mid = (st + dr) / 2;
    if(qa <= mid)
        r1 = qry(st, mid, node * 2, qa, qb);
    if(qb >= mid + 1)
        r2 = qry(mid + 1, dr, node * 2 + 1, qa, qb);
    return max(r1, r2);

}

int main()
{
    ifstream fin ("arbint.in");
    ofstream fout ("arbint.out");
    fin >> n >> m;
    for(int i = 1; i <= n; i++)
    {
        int v;
        fin >> v;
        upd(1, n, 1, i, v);
    }
    for(int i = 1; i <= m; i++)
    {
        int o;
        fin >> o;
        if(o == 1)
        {
            int p, v;
            fin >> p >> v;
            upd(1, n, 1, p, v);
        }
        else
        {
            int a, b;
            fin >> a >> b;
            fout << qry(1, n, 1, a, b) << "\n";
        }
    }
    return 0;
}