using namespace std;
#include<iostream>
#include<fstream>
#include<cstdlib>
#define oo 0x3f3f3f3f
int H[300005],a[100005],full[300005],N,M;
#define common  int m=(l+r)/2, L=2*n, R=L+1

ofstream fout("arbint.out");

void update(int n,int ql,int qr,int l,int r,int v)
{
    if(ql<=l && r<=qr)
    {
        H[n]=v;
        full[n]=1;
        return;

    }
    common;

    if(full[n]==1)
    {
        full[n]=0;
        full[L]=full[R]=1;
        H[L]=H[R]=H[n];
    }

    if(ql<=m) update(L,ql,qr,l,m,v);
    if(qr>=m+1) update(R,ql,qr,m+1,r,v);

    if(full[L]==1 && full[R]==1 && H[L]==H[R]) full[n]=1;
    else full[n]=0;

    H[n]=max(H[L],H[R]);

}

int query(int n,int ql,int qr,int l,int r)
{int x,sol=-oo;
    if(full[n])
     return H[n];
    if(ql<=l && r<=qr)   ///daca [l,r] este inclus in [ql, qr]
      return H[n];

    common;

    if(ql<=m)
    {
        x=query(L,ql,qr,l,m);
        sol=sol>x ? sol :x;
    }

    if(qr>=m+1)
    {
        x=query(R,ql,qr,m+1,r);
        sol=sol>x ? sol :x;


    }
    return sol;

}

inline void build(int n,int l,int r)
{

    if(l>=r) {H[n]=a[l]; full[n]=1; return;}

    common;

    build(L,l,m);
    build(R,m+1,r);

    if(full[L]==1 && full[R]==1 && H[L]==H[R]) full[n]=1;
    else full[n]=0;

    H[n]=max(H[L],H[R]);
}

void cit()
{int i,x,xa,xb;
  ifstream fin("arbint.in");

   fin>>N>>M;
   for(i=1;i<=N;i++)
      fin>>a[i];
   build(1,1,N);
   for(i=1;i<=M;i++)
   {

       fin>>x>>xa>>xb;
       if(x==1)
       {
            update(1,xa,xa,1,N,xb);
       }
       else
        fout<<query(1,xa,xb,1,N)<<"\n";
   }
   fin.close();
}

int main()
{

    cit();

    fout.close();

    return 0;

}