/*
    Those without power, seek us!
    Those with power, fear us!
    We are the Order of the Black Knights!
*/

#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<unsigned 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<ctime>
#include<bitset>
#include<cmath>
#include<iomanip>
#include<set>
#define f cin
#define g cout
#include<queue>
#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 int
#define mod 1000000009LL
#define SQR 350
#define inf 1<<30
#define div fdasfasd
#define hash dsafdsfds
#define od 100003
#define mod  4398042316799LL
#define DIM 60010000
#define base 256
#define bas 255
#define N 100100
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 H[N<<2],v[N],n,m,sol,tip,l,r;

void go(int st,int dr,int po)
{
    if(st==dr)
    {
        H[po]=v[st];
        return ;
    }
    int mij=(st+dr)>>1;
    go(st,mij,po<<1);
    go(mij+1,dr,(po<<1)+1);
    H[po]=max(H[po<<1],H[(po<<1)+1]);
}
void upd(int st,int dr,int po,int p)
{
    if(st==dr)
    {
        H[po]=v[st];
        return ;
    }
    int mij=(st+dr)>>1;
    if(p<=mij)
        upd(st,mij,po<<1,p);
    else
        upd(mij+1,dr,(po<<1)+1,p);
    H[po]=max(H[po<<1],H[(po<<1)+1]);
}
void find(int st,int dr,int po,int l,int r)
{
    if(st>=l&&dr<=r)
    {
        sol=max(sol,H[po]);
        return ;
    }
    int mij=(st+dr)>>1;
    if(l<=mij)
        find(st,mij,po<<1,l,r);
    if(r>mij)
        find(mij+1,dr,(po<<1)+1,l,r);
}
int main ()
{
    f>>n>>m;
    FOR(i,1,n)
    f>>v[i];
    go(1,n,1);
    FOR(i,1,m)
    {
        f>>tip;
        if(!tip)
        {
            f>>l>>r;
            sol=0;
            find(1,n,1,l,r);
            g<<sol<<"\n";
        }
        else
        {
            f>>l>>r;
            v[l]=r;
            upd(1,n,1,l);
        }
    }
    return 0;
}