#include <iostream>
#include <fstream>

using namespace std;

ifstream f ("arbint.in");
ofstream g ("arbint.out");

const int NMAX = 100000;
int n, m, poz, valoare, a, b, sol;
int arb[4 * NMAX + 1];

void update(int, int, int);
void query(int, int, int);

void citeste() {
    f >> n >> m;
    for (int i = 1; i <= n; i++) {
        f >> valoare;
        poz = i;
        update(1, 1, n);
    }
}

void rezolva() {
    int op;
    for (int i = 1; i <= m; i++) {
        f >> op >> a >> b;
        if (op == 0) {
            sol = -1;
            query(1, 1, n);
            g << sol << '\n';
        }
        else {
            valoare = b;
            poz = a;
            update(1, 1, n);
        }
    }
}

int main () {
    citeste();
    rezolva();
    return 0;
}

void update(int nod, int stanga, int dreapta) {
    if (stanga == dreapta) {
        arb[nod] = valoare;
    }
    else {
        int m = (stanga + dreapta) / 2;
        if (poz <= m) update(2 * nod, stanga, m);
        else update(2 * nod + 1, m + 1, dreapta);
        arb[nod] = max(arb[2 * nod], arb[2 * nod + 1]);
    }
}

void query(int nod, int stanga, int dreapta) {
    if (a <= stanga && dreapta <= b) sol = max(sol, arb[nod]);
    else {
        int m = (stanga + dreapta) / 2;
        if (a <= m) query(2 * nod, stanga, m);
        if (m < b) query(2 * nod + 1, m + 1, dreapta);
    }
}