#include <iostream>
#include <fstream>
#include <algorithm>
#include <vector>
using namespace std;
 
class SegTree
{
    int n;
    vector<int> t;
public:
    SegTree(const vector<int> & a)
    {
        n = a.size();
        t.resize(2*n);
        for (int i = 0; i < n; ++i) {
            t[n+i] = a[i];
        }
        for (int i = n-1; i >= 1; --i) {
            t[i] = max(t[2*i], t[2*i+1]);
        }
    }
    void update(int idx, int val)
    {
        idx += n;
        while (t[idx] != val && idx >= 1) {
			t[idx] = val;
            val = max(t[idx], t[idx^1]);
            idx /= 2;
        }
    }
    int getmax(int lo, int hi)
    {
        lo += n;
        hi += n;
        int res = 0;
        while (lo < hi) {
            if (lo%2 == 0) {
                lo /= 2;
            }
            else {
                res = max(res, t[lo]);
                lo = lo/2+1;
            }
            if (hi%2 == 1) {
                hi /= 2;
            }
            else {
                res = max(res, t[hi]);
                hi = hi/2-1;
            }
        }
        if (lo == hi) {
            res = max(res, t[lo]);
        }
        return res;
    }
};
 
int main() {
    ifstream fin("arbint.in");
    ofstream fout("arbint.out");
    int n, m;
    fin >> n >> m;
    vector<int> a(n);
    for (int i = 0; i < n; ++i) {
        fin >> a[i];
    }
    SegTree seg(a);
    for (int i = 0; i < m; ++i) {
        int op;
        fin >> op;
        if (op == 0) {
            int lo, hi;
            fin >> lo >> hi;
            fout << seg.getmax(--lo, --hi) << '\n';
        }
        else {
            int idx, val;
            fin >> idx >> val;
            seg.update(--idx, val);
        }
    }
    return 0;
}