#include <iostream>
#include <stdio.h>
using namespace std;

const int N=100000;

int marb[N],v[N];
int maxim, n, m,cnt=1, sol[N];

int Maxim(int x, int y){
   if(x>y) return x;
   else return y;

}

void afisare(){
    FILE *out;
    out=fopen("arbint.out","w");
    for(int i=1;i<cnt;i++)
    fprintf(out,"%d\n",sol[i]);

}

void query(int inceput, int sfarsit, int nod, int st, int dr){
    int mij=(st+dr)/2;
    if(inceput<=st&&sfarsit>=dr){
        if(maxim<marb[nod]) maxim=marb[nod];
        return;
    }

    if(inceput<= mij) query(inceput , sfarsit, 2*nod,st,mij);
    if(mij<sfarsit) query(inceput, sfarsit, 2*nod+1,mij+1,dr);

}


void schimba(int elem, int poz,int nod, int st, int dr){
     int mij=(st+dr)/2;
     if(st==dr){
          marb[nod]=elem;
          return;
     }

     if (poz<=mij) schimba(elem, poz, 2*nod,  st,   mij);
     else          schimba(elem, poz, 2*nod+1,mij+1,dr );

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


void citire(){
    FILE *in;
    in=fopen("arbint.in","r");
    fscanf(in,"%d%d", &n, &m);
    int a,b,c;
    for(int i=1;i<=n;i++) fscanf(in,"%d",&v[i]);
    for(int i=1;i<=n;i++) schimba(v[i],i,1,1,n);//inserez elem v[i] pe pozitia i incepand de la nodul unu dintre intervalul 1 si n
    for(int i=1;i<=m;i++){
        fscanf(in,"%d%d%d",&c,&a,&b);
        if(c==1) schimba(b,a,1,1,n);
        else    {
                maxim=-1;
                query(a,b,1,1,n);// aflu maximul intre nodul a si b de la nodul 1 in arborele de la 1 la n
                sol[cnt++]=maxim;
            }
    }

}



int main()
{
    citire();
    afisare();
    return 0;
}