#include <iostream>
#include <fstream>
#define MAX 100002
using namespace std;
int n,m,aint[4*MAX],t,a,b,ans;

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

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

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

int update(int nod, int st, int dr, int a, int b){
    if(st == dr){
        aint[nod] = b;
    }else{
        int mid = (st+dr)/2;
        if(a <= mid){
            update(2*nod, st, mid, a, b);
        }else{
            update(2*nod+1, mid+1, dr, a, b);
        }
        aint[nod] = max(aint[2*nod], aint[2*nod+1]);
    }
}

int main()
{
    fin >> n >> m;
    build(1, 1, n);
    while(m--){
        fin >> t >> a >> b;
        if(t == 0){
            ans = 0;
            query(1, 1, n, a, b);
            fout << ans << "\n";
        }else if(t == 1){
            update(1, 1, n, a, b);
        }
    }
    return 0;
}