#include <bits/stdc++.h>
using namespace std;
ifstream fin("arbint.in");
ofstream fout("arbint.out");
const int NMAX = 1e5 + 1;
int n, q, arr[NMAX];

class SegmentTree
{
private:
    int tree[4 * NMAX];
public:
    void build(int node, int st, int dr)
    {
        if(st == dr)
        {
            tree[node] = arr[st];
            return;
        }
        int mid = (st + dr) / 2;
        build(2 * node, st, mid);
        build(2 * node + 1, mid + 1, dr);
        tree[node] = max(tree[2 * node], tree[2 * node + 1]);
    }
    void update(int node, int st, int dr, int poz, int val)
    {
        if(st == dr)
        {
            tree[node] = val;
            arr[poz] = val;
            return;
        }
        int mid = (st + dr) / 2;
        if(poz <= mid)
            update(2 * node, st, mid, poz, val);
        else
            update(2 * node + 1, mid + 1, dr, poz, val);
        tree[node] = max(tree[2 * node], tree[2 * node + 1]);
    }
    int query(int node, int st, int dr, int qst, int qdr)
    {
        if(dr < qst || qdr < st)
            return -1;
        if(qst <= st && dr <= qdr)
            return tree[node];
        int mid = (st + dr) / 2;
        return max(query(2 * node, st, mid, qst, qdr), query(2 * node + 1, mid + 1, dr, qst, qdr));
    }
};
SegmentTree aint;

int main()
{
    fin >> n >> q;
    for(int i = 1; i <= n; i++)
        fin >> arr[i];
    aint.build(1, 1, n);
    while(q--)
    {
        int tip, x, y;
        fin >> tip >> x >> y;
        if(tip == 0)
            fout << aint.query(1, 1, n, x, y) << "\n";
        else
            aint.update(1, 1, n, x, y);
    }

    fin.close();
    fout.close();
    return 0;
}