#include <bits/stdc++.h>
#define maxN 100005

using namespace std;

int n,m,A[4*maxN],v[maxN],sol,op,a,b;

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

void build(int nod,int st,int dr)
{
    if(st == dr)
    {
        A[nod] = v[st];
    }
    else{
        int mid = (st+dr)/2;
        build(2*nod,st,mid);
        build(2*nod+1,mid+1,dr);
        A[nod] = max(A[2*nod],A[2*nod+1]);
    }
}

void query(int nod,int st,int dr,int a,int b)
{
    if(a <= st && dr <=b)
    {
        sol = max(sol,A[nod]);
    }
    else{
        int mid = (st+dr)/2;
        if(a <= mid)
        {
            query(2*nod,st,mid,a,b);
        }
        if(b > mid)
        {
            query(2*nod+1,mid+1,dr,a,b);
        }
    }
}

void update(int nod,int st,int dr,int p,int x)
{
    if(st==dr)
    {
        A[nod] = x;
    }
    else{
        int mid = (st+dr)/2;
        if(p<=mid)
        {
            update(2*nod,st,mid,p,x);
        }
        if(p>mid)
        {
            update(2*nod+1,mid+1,dr,p,x);
        }
        A[nod] = max(A[2*nod],A[2*nod+1]);
    }
}

int main()
{
    fin>>n>>m;
    for(int i = 1;i<=n;i++)
        fin>>v[i];
    build(1,1,n);
    for(int i = 1;i<=m;i++)
    {
        fin>>op>>a>>b;
        if(op==0)
        {
            sol = 0;
            query(1,1,n,a,b);
            fout<<sol<<'\n';
        }
        else{
            update(1,1,n,a,b);
        }
    }
    return 0;
}