#include <iostream>
#include <fstream>

using namespace std;
int maxArb[40020];
int pos,val,maxim = -1;
ifstream fin("arbint.in");
ofstream fout("arbint.out");

inline int Maxim(int a, int b) {
       if ( a > b ) return a;
       return b;
}

void update(int nod, int left, int right, int mponta)
{
    if(left==right)
    {
        maxArb[nod]=mponta;
        return;
    }

        int mid=(left+right)/2;
        if ( pos <= mid )
            update(2*nod,left,mid,mponta);
        else
            update(2*nod+1,mid+1,right,mponta);

        maxArb[nod] = Maxim( maxArb[2*nod], maxArb[2*nod+1] );

}

void query(int nod, int left, int right, int start, int finish)
{

    if(left >= start && right <= finish){
        if(maxArb[nod]>maxim){
            maxim = maxArb[nod];
        }
        return;
    }
    else{

        int mid=(left+right)/2;
        if(start<mid)
            query(2*nod,left,mid,start,finish);
        if(mid<finish)
            query(2*nod+1,mid+1,right,start,finish);

    }

}

int main()
{
    int n,m,i,val,q,a,b,x;

	fin >> n >> m;
	for(i=1;i<=n;++i){
        fin >> x;
        val=x;
        pos = i;
        update(1,1,n,x);
	}


	for(i=1;i<=m;++i){
        fin>>q>>a>>b;
        if(q==1){
            pos = a; val = b;
            update(1,1,n,b);
        }
        else{
            query(1,1,n,a,b);
            fout << maxim << "\n";
            maxim=-1;
        }
	}


    return 0;
}