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

const int MAXN = 100005;

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

int N, M;
int Arb[3 * MAXN];
int pos, val, maxim, a, b;

void Update(int node, int l, int r) {
    if (l == r) {
        Arb[node] = val;
        return;
    }
    int m = (l + r) / 2;
    if (pos <= m) Update(2 * node, l, m);
    else Update(2 * node + 1, m + 1, r);
    Arb[node] = max(Arb[2 * node], Arb[2 * node + 1]);
}

void Query(int node, int l, int r) {
    if (a <= l && r <= b) {
        maxim = max(maxim, Arb[node]);
        return;
    }
    int m = (l + r) / 2;
    if (a <= m) Query(2 * node, l, m);
    if (m < b) Query(2 * node + 1, m + 1, r);
}

int main() {
    fin >> N >> M;
    for (int i = 1; i <= N; ++i) {
        int x;
        fin >> x;
        pos = i;
        val = x;
        Update(1, 1, N);
    }
    for (int type, x, y; M; --M) {
        fin >> type >> x >> y;
        if (type == 1) {
            pos = x;
            val = y;
            Update(1, 1, N);
        }
        else {
            a = x;
            b = y;
            maxim = -1;
            Query(1, 1, N);
            fout << maxim << '\n';
        }
    }
    fin.close();
    fout.close();
    return 0;
}