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

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

int n, m;
int arb[4 * 100000 + 1];

void build(int nod, int st, int dr)
{
    if(st == dr)
        fin >> arb[nod];
    else
    {
        int mid = (st + dr) >> 1;
        build(nod << 1, st, mid);
        build((nod << 1) + 1, mid + 1, dr);
        arb[nod] = max(arb[nod << 1], arb[(nod << 1) + 1]);
    }
}

void update(int nod, int st, int dr, int p, int val)
{
    if(st == dr)
        arb[nod] = val;
    else
    {
        int mid = (st + dr) >> 1;
        if(p <= mid)
            update(nod << 1, st, mid, p, val);
        else update((nod << 1) + 1, mid + 1, dr, p, val);
        arb[nod] = max(arb[nod << 1], arb[(nod << 1) + 1]);
    }
}

int query(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 arb[nod];
    int mid = (st + dr) >> 1;
    return max(query(nod << 1, st, mid, x, y), query((nod >> 1 ) + 1, mid + 1, dr, x, y));
}

int main()
{
    int op, x, y;
    fin >> n >> m;
    build(1, 1, n);
    while(m--)
    {
        fin >> op >> x >> y;
        if(op == 0)
            fout << query(1, 1, n, x, y);
        else update(1, 1, n, x, y);
    }
    fin.close();
    fout.close();
    return 0;
}