#include <bits/stdc++.h>
using namespace std;
ifstream in("arbint.in");
ofstream out("arbint.out");
int tree[400004],pos,y,a,b,mx,n,m,t;
void update(int x,int left,int right)
{
    if(left==right)tree[x]=y;
    else{
        int mid=(left+right)/2;
        if(pos<=mid)update(2*x,left,mid);
        else update(2*x+1,mid+1,right);
        tree[x]=max(tree[2*x+1],tree[2*x]);
    }
}
void query(int x,int left,int right)
{
    if(a<=left && b>=right)mx=max(tree[x],mx);
    else{
        int mid=(left+right)/2;
        if(a<=mid)query(2*x,left,mid);
        if(b>mid)query(2*x+1,mid+1,right);
    }
}
int main()
{
    in>>n>>m;
    for(int i=1;i<=n;i++)
    {
        in>>y;
        pos=i;
        update(1,1,n);
    }
    for(;m;m--)
    {
        in>>t>>a>>b;
        if(t==0)
        {
            mx=-1;
            query(1,1,n);
            out<<mx<<'\n';
        }
        else{
            pos=a;y=b;
            update(1,1,n);
        }
    }
    return 0;
}