#include <iostream>
#include <fstream>

using namespace std;

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

void insert(int arbore[], int x, int poz, int nod, int st, int dr) {
    if (st == dr) {
        arbore[nod] = x;
        return;
    }
    int m = (st + dr) / 2;
    if (poz <= m)
        insert(arbore, x, poz, 2 * nod, st, m);
    else
        insert(arbore, x, poz, 2 * nod + 1, m + 1, dr);
    arbore[nod] = max(arbore[2 * nod], arbore[2 * nod + 1]);
}

int maxim = -1;

void query(int arbore[], int start, int stop, int nod, int st, int dr) {
    if (start <= st && dr <= stop) {
        if (arbore[nod] > maxim)
            maxim = arbore[nod];
        return;
    }
    int m = (st + dr) / 2;
    if(start <= m)
        query(arbore, start, stop, 2 * nod, st, m);
    if(m < stop)
        query(arbore, start, stop, 2 * nod + 1, m + 1, dr);
}
int arbore[1000001], v[1000001];
int main() {
    int n, m, i, x, a, b;
    fin >> n >> m;
    for(i = 1; i <= n; ++i) {
        fin >> x;
        insert(arbore, x, i, 1, 1, n);
    }
    for(i = 0; i <  m; ++i) {
        fin >> x >> a >> b;
        if(x == 0) {
            maxim = -1;
            query(arbore, a, b, 1, 1, n);
            fout << maxim << "\n";
        }
        else {
            insert(arbore, b, a, 1, 1, n);
        }
    }
    return 0;
}