#include <bits/stdc++.h>
#define Nmax  100005

using namespace std;

ifstream f ("arbint.in");
ofstream g ("arbint.out");

int heap[4*Nmax],a,b,i,x,y,n,Max,t;

inline void heapInsert(int val,int poz,int st,int dr,int nod)
{
    if(st == dr)
    {
        heap[nod] = val;
        return;
    }

    int mij = (st + dr) / 2;
    if(poz <= mij)
        heapInsert(val,poz,st,mij,2*nod);
    else heapInsert(val,poz,mij + 1,dr, 2*nod + 1);

    heap[nod] = max(heap[nod*2],heap[nod*2 + 1]);
}

inline void heapQuery(int a,int b,int st,int dr,int nod)
{
    if(a <= st && dr <= b)
    {
        Max = max(Max,heap[nod]);
        return;
    }

    int mij = (st + dr) / 2;
    if(a <= mij)
        heapQuery(a,b,st,mij,2*nod);
    if(b >= mij + 1)
        heapQuery(a,b,mij + 1,dr,2*nod + 1);
}

int main()
{
    f >> n >> t;
    for(i = 1;i <= n;i++)
        f >> x,heapInsert(x,i,1,n,1);

    for(i = 1;i <= t;i++)
    {
        f >> x >> a >> b;
        switch(x)
        {
        case 1:
            heapInsert(b,a,1,n,1);
            break;
        case 0:
            Max = -1;
            heapQuery(a,b,1,n,1);
            g << Max << '\n';
            break;
        }
    }
    return 0;
}