#include <iostream>
#include <fstream>
#include <vector>

using namespace std;

class AInt {
public:
    AInt() = delete;
    AInt(const vector<int> &v, int n) : v(v), n(n), aint(4*n) {
        build(1, 1, n);
    }

    void update(int pos, int newval) {
        update(1, 1, n, pos, newval);
    }

    int query(int left, int right) {
        return query(1, 1, n, left, right);
    }

private:
    int query(int node, int left, int right, int qleft, int qright) {
        if(left == right) {
            return aint[node];
        }
        else {
            int m = (left + right) / 2;

            if(qright <= m) {
                return query(node * 2, left, m, qleft, qright);
            }
            if (m + 1 <= qleft){
                return query(node * 2 + 1, m+1, right, qleft, qright);
            }

            return max(query(node * 2, left, m, qleft, qright),
                       query(node * 2 + 1, m+1, right, qleft, qright));
        }
    }

    void update(int node, int left, int right, int pos, int newval) {
        if(left == right) {
            aint[node] = newval;
        }
        else {
            int m = (left + right) / 2;

            if(pos <= m) {
                update(node * 2, left, m, pos, newval);
            }
            else {
                update(node * 2 + 1, m+1, right, pos, newval);
            }

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

    void build(int node, int left, int right) {
        if(left == right) {
            aint[node] = v[left];
        }
        else {
            int m = (left + right) / 2;

            build(node * 2, left, m);
            build(node * 2 + 1, m+1, right);

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

    vector<int> aint;
    vector<int> v;
    int n;
};

int main() {
    ifstream fin("arbint.in");
    ofstream fout("arbint.out");
    int n, m;

    fin >> n  >> m;
    vector<int> v(n+1);
    for(int i = 1; i <= n; i++) {
        fin >> v[i];
    }
    AInt aint(v, n);
    for(int i = 0; i < m; i++) {
        int op, x, y;
        fin >> op >> x >> y;

        if(op == 1) {
            aint.update(x, y);
        }
        else {
            fout << aint.query(x, y) << '\n';
        }
    }

    return 0;
}