#include <bits/stdc++.h>
using namespace std;
ifstream fin("arbint.in");
ofstream fout("arbint.out");
const int NMAX = 100001;
int n, q, a[NMAX];

struct SegmentTree
{
    int T[4 * NMAX];
    void build(int node, int st, int dr)
    {
        if(st == dr)
        {
            T[node] = a[st];
            return;
        }
        int mid = (st + dr) / 2;
        build(2 * node, st, mid);
        build(2 * node + 1, mid + 1, dr);
        T[node] = max(T[2 * node], T[2 * node + 1]);
    }

    void update(int node, int st, int dr, int poz, int val)
    {
        if(st == dr)
        {
            a[st] = val;
            T[node] = 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);
        T[node] = max(T[2 * node], T[2 * node + 1]);
    }

    int query(int node, int st, int dr, int qst, int qdr)
    {
        if(qdr < st || dr < qst)
            return -1;
        if(qst <= st && dr <= qdr)
            return T[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 >> a[i];
    aint.build(1, 1, n);
    while(q--)
    {
        int tip, a, b;
        fin >> tip >> a >> b;
        if(tip == 0)
            fout << aint.query(1, 1, n, a, b) << "\n";
        else
            aint.update(1, 1, n, a, b);
    }

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