using namespace std;
#include<iostream>
#include<fstream>
#define nmax 100005
#define oo 0x3f3f3f3f
#define common int m=(l+r)/2, L=2*n, R=L+1
ofstream fout("arbint.out");
int a[nmax],H[nmax*3],full[nmax*3];
int N,M;

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])
    {
        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]+ full[R]==2 && H[R]==H[L]) 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 sol=-oo,x;
    if(full[n])
    {
        return H[n];

    }
    if(ql<=l && r<=qr)
    {
        return H[n];

    }

    common;

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

void build(int n,int l,int r)
{
    if(l>=r) {H[n]=l; full[n]=1; return;}

    common;

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

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

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


}


void cit()
{int i,c,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>>c>>xa>>xb;
        if(c==1)

           update(1,xa,xa,1,N,xb);
          else
           fout<<query(1,xa,xb,1,N);


    }

}

int main()
{

    cit();

    fout.close();

    return 0;

}