#include <iostream>
#include <stdio.h>

using namespace std;

int m,n;
int MaxArb[400066];
int start,finish,val,poz,maxim;

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

void update (int nod, int left, int right)
 {
     if (left==right)
     {
         MaxArb[nod]=val;
         return;
     }
     int div=(left+right)/2;
     if (poz<=div)
        update(2*nod,left,div);
     else
        update(2*nod+1,div+1,right);
    MaxArb[nod]=mxm(MaxArb[2*nod],MaxArb[2*nod+1]);

 }
 void query (int nod, int left, int right)
 {
     if (start<=left && right<=finish)
        {
            if (maxim<MaxArb[nod])
            maxim=MaxArb[nod];
            return;
        }
    int div=(left+right)/2;
    if (start<=div) query(2*nod,left,div);
    if (div+1<=finish) query (2*nod+1, div+1, right);
 }


int main()
{
    freopen("arbint.in","r",stdin);
    freopen("arbint.out","w",stdout);
    int x,a,b;
    scanf ("%d %d", &n,&m);
    for(int i=1;i<=n;i++)
    {
        scanf("%d",&x);
        poz=i;
        val=x;
        update(1,1,n);
    }
    for (int i=1;i<=m;i++)
    {
        scanf("%d %d %d",&x,&a,&b);
        if (x==0)
        {
            maxim=-1;
            start=a;
            finish=b;
            query(1,1,n);
            printf("%d\n",maxim);
        }
        else
        {
            poz=a;
            val=b;
            update(1,1,n);
        }
    }
    return 0;
}