#include <iostream>
#include <fstream>
using namespace std;

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

const int dim = 100001;

int arb[4 * dim];

void update(int node, int st, int dr, int pos, int val) {

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

    int m = (st + dr) / 2;

    if (pos <= m) {
        update(2 * node, st, m, pos, val);
    } else {
        update(2 * node + 1, m + 1, dr, pos, val);
    }

    arb[node] = max(arb[2 * node], arb[2 * node + 1]);
}

void query(int nod, int st, int dr, int a, int b, int &maxim) {
    if (a <= st && dr <= b) {
        maxim = max(maxim, arb[nod]);
        return;
    }
    int m = (st + dr) / 2;
    if (a <= m) {
        query(2 * nod, st, m, a, b, maxim);
    }
    if (b >= m + 1) {
        query(2 * nod + 1, m + 1, dr, a, b, maxim);
    }
}

int main()
{
    int n, q, i, x, t, a, b, maxim;

    in >> n >> q;
    for (i = 1; i <= n; i++) {
        in >> x;
        update(1, 1, n, i, x);
    }

    for (i = 1; i <= q; i++) {
        in >> t >> a >> b;
        if (t == 0) {
            maxim = -1;
            query(1, 1, n, a, b, maxim);
            out << maxim << "\n";
        } else {
            update(1, 1, n, a, b);
        }
    }


    return 0;
}