/*
    Look at me!
    Look at me!
    Look at how large the monster inside me has become!
*/

#include<fstream>
#include<cstdio>
#include<map>
#include<set>
#define FIT(a,b) for(vector<int >::iterator a=b.begin();a!=b.end();a++)
#define FITP(a,b) for(vector<pair<int,int> >::iterator a=b.begin();a!=b.end();a++)
#define RIT(a,b) for(vector<int>::reverse_iterator a=b.end();a!=b.begin();++a)
#include<stack>
#define ROF(a,b,c) for(int a=b;a>=c;--a)
#include<vector>
#include<algorithm>
#define FOR(a,b,c) for(int a=b;a<=c;++a)
#define REP(a,b) for(register int a=0;a<b;++a)
#include<cstring>
#include<bitset>
#include<cmath>
#include<iomanip>
#define f cin
#define g cout
#include<queue>
#define W freopen("a.in","r",stdin);freopen("a.out","w",stdout);
#define INF 0x3f3f3f3f
#define debug cerr<<"OK";
#define pii pair<int,int>
#define mp make_pair
#define pb push_back
#define fi first
#define se second
#define ll long long
#define ull unsigned long long
#define eps 1.e-9
#define BUFMAX 10100100
#define NM 2000010
#define N 100010
#define mod 1000000007
using namespace std;
/*int dx[]={0,0,0,1,-1};
int dy[]={0,1,-1,0,0};*/
ifstream f("arbint.in");
ofstream g("arbint.out");

int lef[NM],rig[NM],H[NM],v[N],R[N],n,m,t,up,k,nods,p,x,l,r,sol;
void go(int nod,int st,int dr)
{
    if(st==dr)
    {
        H[nod]=v[st];
        return ;
    }
    int mij=(st+dr)>>1;
    lef[nod]=++nods;
    go(lef[nod],st,mij);
    rig[nod]=++nods;
    go(rig[nod],mij+1,dr);
    H[nod]=max(H[lef[nod]],H[rig[nod]]);
}
void atr(int cur,int old)
{
    //aici copiez intr-un nod un altul
    H[cur]=H[old];
    lef[cur]=lef[old];
    rig[cur]=rig[old];
}
void upd(int old,int cur,int st,int dr,int p,int x)
{
    if(st==dr)
    {
        H[cur]=x;
        return ;
    }
    int mij=(st+dr)>>1;
    //cand ma duc pe un fiu fac nod nou si copiez TOT din nodul vechi in el
    if(p<=mij)
    {
        lef[cur]=++nods;
        atr(lef[cur],lef[old]);
        upd(lef[old],lef[cur],st,mij,p,x);
    }
    else
    {
        rig[cur]=++nods;
        atr(rig[cur],rig[old]);
        upd(rig[old],rig[cur],mij+1,dr,p,x);
    }
    H[cur]=max(H[lef[cur]],H[rig[cur]]);
}
void find(int cur,int st,int dr,int l,int r)
{
    if(st>=l&&dr<=r)
    {
        sol=max(sol,H[cur]);
        return ;
    }
    int mij=(st+dr)>>1;
    if(l<=mij)
        find(lef[cur],st,mij,l,r);
    if(r>mij)
        find(rig[cur],mij+1,dr,l,r);
}
int main ()
{
    f>>n>>m;
    FOR(i,1,n)
    f>>v[i];
    ++nods;
    R[0]=nods; //radacina dupa 0 updateuri
    go(R[0],1,n);

    FOR(i,1,m)
    {
        f>>t;
        if(t)
        {
            ++up; //mai apare un update
            f>>p>>x;
            k=up-1; //k asta poate fi oricat intre 1 si up-1, dar il setez up-1 ca sa mearga pe testele de la arbint
            R[up]=++nods;
            atr(nods,R[k]);
            upd(R[k],R[up],1,n,p,x);
        }
        else
        {
            f>>l>>r;
            k=up; //la fel si aici, poate fi oricat
            sol=0;
            find(R[k],1,n,l,r);
            g<<sol<<"\n";
        }
    }
    return 0;
}