#include <bits/stdc++.h>
#define mp make_pair
#define pb push_back
#define INF numeric_limits<int>::max()
#define int64 long long
using namespace std;
ifstream in("arbint.in");
ofstream out("arbint.out");
vector<int> tree;
int n,sol;
void update(int x,int left,int right,int pos,int val)
{
    if(left==right)
        tree[x]=val;
    else{
        int mid=(left+right)/2;
        if(pos<=mid)
            update(2*x,left,mid,pos,val);
        else
            update(2*x+1,mid+1,right,pos,val);
        tree[x]=max(tree[2*x],tree[2*x+1]);
    }
}
void query(int x,int left,int right,int a,int b)
{
    if(a<=left && b>=right)
        sol=max(sol,tree[x]);
    else{
        int mid=(left+right)/2;
        if(a<=mid)
            query(2*x,left,mid,a,b);
        if(b>mid)
            query(2*x+1,mid+1,right,a,b);
    }
}
int main()
{
    int Q;
    in>>n>>Q;
    tree=vector<int> (4*n+1);
    for(int i=1;i<=n;i++)
    {
        int x;
        in>>x;
        update(1,1,n,i,x);
    }
    for(;Q;Q--)
    {
        int t,x,y;
        in>>t>>x>>y;
        if(t==1)
            update(1,1,n,x,y);
        else{
            sol=0;
            query(1,1,n,x,y);
            out<<sol<<'\n';
        }
    }
    return 0;
}