#include <bits/stdc++.h>

using namespace std;
#define RR 50003
//#define CC 250000
#define N 50003
#define oo 1000000000
#define pp pair<int,int>
#define RRR ios_base::sync_with_stdio(false);cin.tie(0);

int ar[200001];
int val[200001];
void build(int node, int s, int e)
{

    if (s == e)
    {
        ar[node] = val[s];
    }else
    {
        int mid = (s+e) / 2;
        build(2*node,s,mid);
        build(2*node+1,mid+1,e);
        ar[node] = max(ar[node*2] , ar[node*2+1]);
    }
}

void update(int node, int s,int e,int idx, int v)
{
    if (s == e)
    {
      //  val[idx]=v;
        ar[node]=v;
    }else
    {
        int mid = (s+e)/2;
        if (idx <= mid) update(2*node,s,mid,idx,v);
        else
            update(2*node+1,mid+1,e,idx,v);
        ar[node] = max(ar[2*node] , ar[2*node+1]);
    }
}
int maxim = -1;
void query(int node, int s, int e,int l, int r)
{

    if (l <= s and  e <= r)
    {
        if (maxim < ar[node]) maxim = ar[node];
        return ;
    }
    int mid = (s+e)/2;

    if (l<=mid) query(node*2,s,mid,l,r);
    if (r>mid) query(node*2+1,mid+1,e,l,r);

}

int main()
{
    RRR
    freopen("arbint.in","r",stdin);
    freopen("arbint.out","w",stdout);
    int m,n;
    cin >> n >> m;
    for (int i=1;i<=n;i++)
    {
        cin >> val[i];
        update(1,1,n,i,val[i]);
    }
   // build(1,1,n);
    for (int i=0;i<m;i++)
    {
        int a,b,c;
        cin >> a >> b >> c;
        if (a == 0)
        {
            maxim = -1;
            query(1,1,n,b,c);
            cout << maxim<<"\n";
        }
        else update(1,1,n,b,c);
    }
    return 0;
}