#include <iostream>
#include<fstream>
using namespace std;
ifstream in("arbint.in");
ofstream out("arbint.out");

int value_count,query_count;
int values[100000];
int node_values[262144];

void read_values()
{
    in>>value_count>>query_count;
    for(int i=0; i<value_count; i++)
        in>>values[i];
}

int create_tree(int left,int right,int index)
{
    int middle=(left+right)/2;
    if(left==right)
    {
        node_values[index]=values[left];
    }
    else
    {
        int here=max(create_tree(left,middle,2*index),create_tree(middle+1,right,2*index+1));
        node_values[index]=here;
    }
    return node_values[index];

}


int get_max_in_interval(int a,int b,int left,int right,int index)
{
    if(left>=a && right<=b)
    {
        return node_values[index];
    }

    int middle=(left+right)/2;

    int to_return=-1;

    if(a<=middle)
    {
        to_return=max(to_return,get_max_in_interval(a,b,left,middle,index*2));

    }
    if(b>middle)
    {
        to_return=max(to_return,get_max_in_interval(a,b,middle+1,right,index*2+1));
    }

    return to_return;


}
void set_value(int left,int right,int index,int value,int here)
{
    if(left>=right)
    {
        node_values[here]=value;
    }
    else
    {

        int middle=(left+right)/2;

        if(index<=middle)
        {
            set_value(left,middle,index,value,here*2);
        }
        else
        {
            set_value(middle+1,right,index,value,here*2+1);
        }

        node_values[here]=max(node_values[here*2+1],node_values[here*2]);
    }
}


int get_max(int a,int b)
{
    return get_max_in_interval(a,b,0,value_count-1,1);
}
void create_interval_tree()
{
    create_tree(0,value_count-1,1);
}

void set_value_at(int index,int value)
{
    set_value(0,value_count-1,index,value,1);
}
void solve_queries()
{
    int query,a,b,to_return;
    for(int i=0; i<query_count; i++)
    {
        in>>query>>a>>b;
        if(query==0)
        {
            to_return=get_max(a-1,b-1);
            out<<to_return<<'\n';
        }
        else
        {
            set_value_at(a-1,b);
        }
    }
}
int main()
{
    read_values();
    create_interval_tree();
    solve_queries();
    return 0;
}