#include <bits/stdc++.h>
#include <assert.h>
#define FAST std::ios_base::sync_with_stdio(false); cin.tie(0); cout.tie(0);
using namespace std;
const int MAX=100001;
int n,m,start,finish,val,pos,maxx;
int arb[4*MAX+66];
ifstream in("arbint.in");
ofstream out("arbint.out");
void update(int,int,int);
int query(int,int,int,int,int);
int main()
{
    int x,a,b;
    in>>n>>m;
    for(int i=1;i<=n;++i){
        in>>x;
        pos=i;
        val=x;
        update(1,1,n);
    }
    for(int i=1;i<=m;++i){
        in>>x>>a>>b;
        if(x==0){
            maxx=-1;
            start=a;
            finish=b;
            maxx=query(1,1,n,start,finish);
            out<<maxx<<endl;
        }
        else{
            pos=a;
            val=b;
            update(1,1,n);
        }
    }
    return 0;
}
void update(int nod,int left,int right){
if(left==right){
    arb[nod]=val;
    return;
}
int mid=(left+right)/2;
if(pos<=mid)
    update(2*nod,left,mid);
else
    update(2*nod+1,mid+1,right);
arb[nod]=max(arb[2*nod],arb[2*nod+1]);
}
int query(int nod,int left,int right,int start,int finish)
{
if(start==left and finish==right)
	return arb[nod];
int mid=(left+right)/2;
if(finish<=mid)
	return query(2*nod,left,mid,start,finish);
if(left>mid)
	return query(2*nod+1,mid+1,right,start,finish);
if(start<=mid&&finish>mid)
	return max(query(2*nod,left,mid,start,mid),query(2*nod+1,mid+1,right,mid+1,finish))+1;
}