#include <fstream>
#include <vector>
#include <algorithm>

using namespace std;

template<class IntType>
class SegmentTree {
  public:
    SegmentTree(const vector<IntType> &values) {
        for (size = 1; size < int(values.size()); size *= 2);
        tree = vector<IntType>(2 * size + 1, 0);
        for (int x = 0; x < int(values.size()); ++x)
            tree[size + x] = values[x];
        for (int x = size - 1; x > 0; --x)
            tree[x] = max(tree[2 * x], tree[2 * x + 1]);
    }

    void Update(int where, const IntType value) {
        tree[where += size] = value;
        for (where /= 2; where > 0; where /= 2)
            tree[where] = max(tree[2 * where], tree[2 * where + 1]);
    }

    IntType Query(int from, int to) {
        IntType answer = 0;
        from += size;
        to += size;
        while (from <= to) {
            answer = max(answer, max(tree[from], tree[to]));
            from = (from + 1) / 2;
            to = (to - 1) / 2;
        }
        return answer;
    }

  private:
    int size;
    vector<IntType> tree;
};

int main() {
    ifstream cin("arbint.in");
    ofstream cout("arbint.out");
    int n, q;
    vector<int> values;
    cin >> n >> q;
    values.resize(n);
    for (int i = 0; i < n; ++i)
        cin >> values[i];
    SegmentTree<int> tree(values);
    for (; q > 0; --q) {
        int type, x, y;
        cin >> type >> x >> y;
        if (type == 1)
            tree.Update(x - 1, y);
        else
            cout << tree.Query(x - 1, y - 1) << "\n";
    }
    cin.close();
    cout.close();
    return 0;
}