#include <iostream>
#include <fstream>
#include <cmath>
#include <algorithm>
#include <cstdlib>
#include <ctime>
#include <cstring>

using namespace std;

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

const int N = 1 << 18;
const int INF = 1 << 30;

int arb[N];

void constr(int p, int st, int dr) {
    
    if (st == dr) {
        fin >> arb[p];
    }
    else {
        int m = (st + dr) / 2, fs = 2 * p, fd = 2 * p + 1;
        constr(fs, st, m);
        constr(fd, m + 1, dr);
        arb[p] = max(arb[fs], arb[fd]);
    }

}

int maxx(int p, int st, int dr, int a, int b) {

    if (a <= st && dr <= b) {
        return arb[p];
    }

    int m = (st + dr) / 2, fs = 2 * p, fd = 2 * p + 1;
    int rez_st = -INF, rez_dr = -INF;

    if (a <= m) {
        rez_st = maxx(fs, st, m, a, b);
    }
    if (m + 1 <= b) {
        rez_dr = maxx(fd, m + 1, dr, a, b);
    }

    return max(rez_st, rez_dr);

}

void actualizare(int p, int st, int dr, int poz, int val) {

    if (st == dr) {
        arb[p] = val;
        return;
    }

    int m = (st + dr) / 2, fs = 2 * p, fd = 2 * p + 1;

    if (poz <= m) {
        actualizare(fs, st, m, poz, val);
    }
    else {
        actualizare(fd, m + 1, dr, poz, val);
    }

    arb[p] = max(arb[fs], arb[fd]);

}

int main()
{
    int n, nq;
    fin >> n >> nq;

    constr(1, 1, n);

    for (int i = 1; i <= nq; i++) {
        int c;
        fin >> c;

        if (c == 0) {
            int a, b;
            fin >> a >> b;
            fout << maxx(1, 1, n, a, b) << "\n";
        }
        else{
            int poz, val;
            fin >> poz >> val;
            actualizare(1, 1, n, poz, val);
        }
    }

    return 0;
}