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

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

const int maxn = 1e5 + 5;
int B[maxn], V[maxn], rad, n, q;

inline int Bucket(int i) {
    return i / rad;
}

inline int First(int i) {
    return i * rad;
}

void Update (int pos, int val) {
    int i = Bucket(pos), j;
    if (V[pos] == B[i]) {
        V[pos] = 0;
        B[i] = 0;
        for (j = First(i); j < First(i + 1); j++) {
            B[i] = max(B[i], V[j]);
        }
    }
    V[pos] = val;
    B[i] = max(B[i], val);
}

int Query (int x, int y) {
    int ans = 0, i;
    int left = Bucket(x);
    int right = Bucket(y);
    for (i = left + 1; i < right; i++) {
        ans = max(ans, B[i]);
    }
    if (ans < B[left]) {
        for (i = x; i <= y && i < First(left + 1); i++) {
            ans = max(ans, V[i]);
        }
    }
    if (ans < B[right]) {
        for (i = max(First(right), x); i <= y; i++) {
            ans = max(ans, V[i]);
        }
    }
    return ans;
}

int main() {
    ios_base :: sync_with_stdio(false);
    int op, x, y;
    fin >> n >> q;
    rad = sqrt(n);
    for (int i = 1; i <= n; i++) {
        fin >> V[i];
        if (V[i] > B[Bucket(i)]) B[Bucket(i)] = V[i];
    }
    while (q--) {
        fin >> op >> x >> y;
        if (op == 1) Update(x, y);
        else fout << Query(x, y) << "\n";
    }
    return 0;
}