#include <bits/stdc++.h>

using namespace std;
const int NMAX = 1e5;

int tree[4 * NMAX + 1], v[NMAX + 1], ans;

void query(int node, int st, int dr, int a, int b) {
    if (a <= st && dr <= b) {
        ans = max(ans, tree[node]);
        return;
    }

    int mid = (st + dr)/2;
    if (a <= mid) {
        query(node*2, st, mid, a, b);
    }
    if (b > mid) {
        query(node*2+1, mid+1, dr, a, b);
    }
}

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

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

void dfs(int node, int st, int dr) {
    if (st == dr) {
        tree[node] = v[st];
        return; 
    }

    int mid = (st + dr)/2;
    dfs(node*2, st, mid);
    dfs(node*2 + 1, mid+1, dr);
    tree[node] = max(tree[node*2], tree[node*2+1]);
}

int main() {
    int n, m;
    freopen("arbint.in", "r", stdin);
    freopen("arbint.out", "w", stdout);
    cin >> n >> m;
    for (int i = 1; i <= n; i++) {
        cin >> v[ i ];
    }

    dfs(1, 1, n);
    while (m--) {
        int q, a, b;
        cin >> q >> a >> b;
        if (q == 0) {
            ans = -1;
            query(1, 1, n, a, b);
            cout << ans << '\n';
        }
        else {
            update(1, 1, n, b, a);
        }
    }
}