#include <bits/stdc++.h>
#define mp make_pair
#define pb push_back
#define pf push_front
#define ll long long
#define ull unsigned long long
#define x first
#define y second
#define pi pair<int,int>
#define pl pair<ll,ll>
#define EPSILON 0.000001

using namespace std;
ifstream fin("arbint.in");
ofstream fout("arbint.out");

const ll NMAX=4e5+5,INF=1e18,MOD=104659,MMAX=1e2+5,inf=INT_MAX;

int N,M;
int val,pos,st,dr,maxim;
int aint[NMAX];

void update(int nod,int left,int right)
{
    if(left==right)
    {
        aint[nod]=val;
        return;
    }
    int mid=(left+right)/2;
    if(pos<=mid)update(2*nod,left,mid);
    else update(2*nod+1,mid+1,right);
    aint[nod]=max(aint[2*nod],aint[2*nod+1]);
}
void querry(int nod,int left,int right)
{
    if(st<=left&&right<=dr)
    {
        maxim=max(maxim,aint[nod]);
        return;
    }
    int mid=(left+right)/2;
    if(st<=mid)querry(2*nod,left,mid);
    if(mid<dr)querry(2*nod+1,mid+1,right);
}

int main()
{
    fin>>N>>M;
    for(int i=1;i<=N;i++)
    {
        fin>>val;
        pos=i;
        update(1,1,N);
    }
    for(int q=1;q<=M;q++)
    {
        int task,a,b;
        fin>>task>>a>>b;
        if(task==0)
        {
            maxim=-1;
            st=a;
            dr=b;
            querry(1,1,N);
            fout<<maxim<<'\n';
        }
        else
        {
            pos=a;
            val=b;
            update(1,1,N);
        }
    }
    return 0;
}