#include <bits/stdc++.h>

using namespace std;

const int nmax = 100005;
int n, test, v[nmax], aint[nmax*4];

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

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

int query(int nod, int st, int dr, int l, int r)
{
    if(st >= l && dr <= r)
        return aint[nod];
    int mid = (st+dr)/2, ans = -2000000000;
    if(mid >= l)
        ans = query(nod*2, st, mid, l, r);
    if(mid+1 <= r)
        ans = max(ans, query(nod*2+1, mid+1, dr, l, r));
    return ans;
}

int main()
{
    ifstream fin ("arbint.in");
    ofstream fout ("arbint.out");
    fin >> n >> test;
    for (int i = 1; i <= n; ++i)
        fin >> v[i];
    build(1, 1, n);
    while(test--){
        int t, a, b;
        fin >> t >> a >> b;
        if(t == 1)
            update(1, 1, n, a, b);
        else fout << query(1, 1, n, a, b) << "\n";
    }
    return 0;
}