#include <fstream>
#include <vector>
using namespace std;
ifstream cin("arbint.in");
ofstream cout("arbint.out");
const int Nmax = 100001;
int n, m, x, y, c, v[Nmax], tree[4*Nmax], ans, pos, val, start, fin;
void build(int node, int left, int right)
{
    if(left == right)
    {
        tree[node] = v[left];
        return;
    }
    int mij = (left + right) / 2;
    build(2 * node, left, mij);
    build(2*node + 1, mij + 1, right);
    tree[node] = max(tree[2*node], tree[2*node + 1]);
}
void update(int node, int left, int right)
{
    if(left == right)
    {
        tree[node] = val;
        return;
    }
    int mij = (left + right) / 2;
    if(pos <= mij)
        update(2*node, left, mij);
    else
        update(2*node + 1, mij+1, right);
    tree[node] = max(tree[2*node], tree[2*node + 1]);
}
void querry(int node, int left, int right)
{
    if(start <= left && right <= fin)
    {
        ans = max(ans, tree[node]);
        return;
    }
    int mij = (left + right) / 2;
    if(start <= mij)
        querry(2 * node, left, mij);
    if(mij < fin)
        querry(2 * node + 1, mij + 1, right);
}
int main()
{
    cin >> n >> m;

    for(int i=1; i<=n; i++)
        cin >> v[i];
    build(1, 1, n);
    while(m--)
    {
        cin >> c;
        if(c == 0)
        {
            ans = 0;
            cin >> start >> fin;
            querry(1, 1, n);
            cout << ans << '\n';
        }
        else
        {
            cin >> pos >> val;
            update(1, 1, n);
        }

    }
    return 0;
}