#include <fstream>
using namespace std;

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

int v[262144];
int n,m,max1;

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

void actualizare(int p,int val,int nod,int st,int dr)
{
    if(st==dr)
    {
        v[nod]=val;
        return;
    }
    else
    {
        int mij=(st+dr)/2;
        if(p<=mij)
            actualizare(p,val,2*nod,st,mij);
        else
            actualizare(p,val,2*nod+1,mij+1,dr);
        v[nod]=maxim(v[2*nod],v[2*nod+1]);
    }
}

void interogare(int nod,int st,int dr,int a,int b) //interogare interval [st,dr]
{
    if(st<=a && b<=dr)
    {
        if(max1<v[nod])
            max1=v[nod];
        return;
    }
    int mij=(a+b)/2;
    if(st<mij)
        interogare(2*nod,st,dr,a,mij);
    if(mij<dr)
        interogare(2*nod+1,st,dr,mij+1,b);
}

int main()
{
    int val,t,dela,panala,p;
    fscanf(f,"%d%d",&n,&m);
    for(int i=1;i<=n;i++)
    {
        fscanf(f,"%d",&val);
        actualizare(i,val,1,1,n);
    }
    for(int i=1;i<=m;i++)
    {
        fscanf(f,"%d",&t);
        if(t==0)
        {
            fscanf(f,"%d%d",&dela,&panala);
            max1=-1;
            interogare(1,dela,panala,1,n);
            fprintf(g,"%d\n",max1);
        }
        else
        {
            fscanf(f,"%d%d",&p,&val);
            actualizare(p,val,1,1,n);
        }
    }
    return 0;
}