#include <cmath>
#include <cstdio>
#include <iostream>

#define MaxN 100005
#define EPS 1e-12

using namespace std;

int T[3 * MaxN], v[MaxN], N, M;

void build(int node, int st, int dr) {
    if (st == dr) {
        T[node] = v[st];
    } else {
        int mid = (st + dr) / 2;
        build(2 * node, st, mid);
        build(2 * node + 1, mid + 1, dr);
        T[node] = max(T[2 * node], T[2 * node + 1]);
    }
}

void update(int node, int st, int dr, int pos, int val) {
    if (st == dr) {
        T[node] = val;
    } else {
        int mid = (st + dr) / 2;
        if (pos <= mid) {
            update(2 * node, st, mid, pos, val);
        } else {
            update(2 * node + 1, mid + 1, dr, pos, val);
        }
        T[node] = max(T[2 * node], T[2 * node + 1]);
    }
}

int query(int node, int st, int dr, int start, int end) {
    if (start <= st && dr <= end) {
        return T[node];
    } else {
        int mid = (st + dr) / 2;
        int ans = -1;
        if (start <= mid) {
            ans = max(ans, query(2 * node, st, mid, start, end));
        }
        if (mid + 1 <= end) {
            ans = max(ans, query(2 * node + 1, mid + 1, dr, start, end));
        }
        return ans;
    }
}

int main() {
    freopen("arbint.in", "r", stdin);
    freopen("arbint.out", "w", stdout);

    cin >> N >> M;

    for (int i = 1; i <= N; i++) {
        cin >> v[i];
    }

    build(1, 1, N);

    for (int i = 1; i <= M; i++) {
        int tip, a, b;
        cin >> tip >> a >> b;

        if (tip == 1) {
            update(1, 1, N, a, b);
        } else {
            cout << query(1, 1, N, a, b) << endl;
        }
    }

    return 0;
}