#include <cstdio>
#include <iostream>

using namespace std;
int a[270010];
int sol;
FILE *fin=fopen ("arbint.in","r");
FILE *fout=fopen ("arbint.out","w");
void build (int nod,int st,int dr){
    int mid;
    if (st==dr){
        fscanf (fin,"%d",&a[nod]);
        //a[nod]=v[st];
        //if (nod>270000)
          //  printf ("%d ",st);
    }
    else {
        mid=(st+dr)/2;
        build (2*nod,st,mid);
        build (2*nod+1,mid+1,dr);
        a[nod]=max(a[2*nod],a[2*nod+1]);
    }
}
void update (int nod,int st,int dr,int x,int y){
    int mid;
    if (st==dr)
        a[nod]=y;
    else {
        mid=(st+dr)/2;
        if (x<=mid)
            update (2*nod,st,mid,x,y);
        if (x>mid)
            update (2*nod+1,mid+1,dr,x,y);
        a[nod]=max(a[2*nod],a[2*nod+1]);
    }
}
void query (int nod,int st,int dr,int x,int y){
    int mid;
    if (st>=x && y>=dr)
        sol=max(sol,a[nod]);
    else {
        mid=(st+dr)/2;
        if (x<=mid)
            query (2*nod,st,mid,x,y);
        if (mid+1<=y)
            query (2*nod+1,mid+1,dr,x,y);
    }
}
int main()
{
    int n,m,i,cer,x,y;
    fscanf (fin,"%d%d",&n,&m);
    //for (i=1;i<=n;i++)
      //  fscanf (fin,"%d",&v[i]);
    build (1,1,n);
    for (i=1;i<=m;i++){
        fscanf (fin,"%d%d%d",&cer,&x,&y);
        if (cer==1)
            update (1,1,n,x,y);
        else {
            sol=0;
            query (1,1,n,x,y);
            fprintf (fout,"%d\n",sol);
        }
    }
    return 0;
}