#include <fstream>
#include <vector>
#include <algorithm>
using namespace std;

void change_rec(vector<int> &arb, int nod, int st, int dr, int pos, int value)
{
    if (st == dr /* == pos */) {
        arb[nod] = value;
    }
    else {
        int mij = (st + dr) / 2;

        if (pos <= mij) {
            change_rec(arb, 2*nod, st, mij, pos, value);
        }
        else {
            change_rec(arb, 2*nod+1, mij+1, dr, pos, value);
        }

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

int query_rec(vector<int> &arb, int nod, int st, int dr, int a, int b)
{
    if (a <= st && dr <= b)
        return arb[nod];
    else {
        int mij = (st+dr) / 2;

        int maxim = -1;

        if (a <= mij) {
            maxim = max(maxim, query_rec(arb, 2*nod, st, mij, a, b));
        }

        if (b >= mij + 1) {
            maxim = max(maxim, query_rec(arb, 2*nod+1, mij+1, dr, a, b));
        }

        return maxim;
    }
}

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

    int n, m;
    fin >> n >> m;

    vector<int> arb(4*n, 0);

    for (int i = 1; i <= n; ++i) {
        int x;
        fin >> x;
        change_rec(arb, 1, 1, n, i, x);
    }

    for (int i = 0; i < m; ++i)
    {
        int op, a, b;
        fin >> op >> a >> b;

        if (op == 0)
            fout << query_rec(arb, 1, 1, n, a, b) << "\n";
        else
            change_rec(arb, 1, 1, n, a, b);
    }

    return 0;
}