#include <cstdio>
#include <iostream>
#define nmax 100005
using namespace std;

FILE *f=fopen("arbint.in","r");
FILE *g=fopen("arbint.out","w");

int n,m,v[nmax],arbore[nmax<<2],maxim;

void build(int nod,int poz,int val,int st,int dr)
{
    int mid=(st+dr)/2;
    if (st==poz&&st==dr)
    {
        arbore[nod]=val;
        return;
    }
    if (poz<=mid)
        build(nod*2,poz,val,st,mid);
    else
        build(nod*2+1,poz,val,mid+1,dr);
    arbore[nod]=max(arbore[nod*2],arbore[nod*2+1]);
}

void query(int nod,int left,int right,int st,int dr)
{
    int mid=(st+dr)/2;
    if (st>=left&&dr<=right)
    {
        maxim=max(maxim,arbore[nod]);
        return;
    }
    if (left>dr||right<st)
        return;
    query(nod*2,left,right,st,mid);
    query(nod*2+1,left,right,mid+1,dr);
}

void read()
{
    fscanf(f,"%d %d",&n,&m);
    for (int i=1;i<=n;++i)
    {
        fscanf(f,"%d",&v[i]);
        build(1,i,v[i],1,n);
    }
    for (int i=1;i<=m;++i)
    {
        int a,b,c;
        fscanf(f,"%d %d %d",&a,&b,&c);
        if (a==1)
            build(1,b,c,1,n);
        else
        {
            maxim=-1;
            query(1,b,c,1,n);
            fprintf(g,"%d\n",maxim);
        }
    }
}

int main()
{
    read();
    return 0;
}