#include <bits/stdc++.h>
using namespace std;

ifstream f ("arbint.in");
ofstream fout ("arbint.out");

const int maxn = 1e5 + 5;
int T[maxn << 1], n;

class Scanner {
private:
    static const int maxb = 1 << 17;
    char Buff[maxb];
    int i = maxb - 1;
    void Advance() {
        if (++i == maxb) {
            i = 0;
            f.read(Buff, maxb);
        }
    }
public:
    inline Scanner& operator >> (int &val) {
        while (!(isdigit(Buff[i]))) {
            Advance();
        }
        val = 0;
        while (isdigit(Buff[i])) {
            val = (val << 1) + (val << 3) + (Buff[i] - '0');
            Advance();
        }
        return *this;
    }
} fin;

void Build () {
    for (int i = n - 1; i > 0; i--) {
        T[i] = max(T[i << 1], T[i << 1 | 1]);
    }
}

void Update (int pos, int val) {
    pos += n - 1;
    for (T[pos] = val; pos > 1; pos >>= 1) {
        T[pos >> 1] = max(T[pos], T[pos ^ 1]);
    }
}

int Query (int left, int right) {
    int ans = -1;
    left += n - 1;
    right += n - 1;
    while (left <= right) {
        ans = max(ans, max(T[left++], T[right--]));
        left >>= 1;
        right >>= 1;
    }
    return ans;
}

int main () {
    ios_base :: sync_with_stdio(false);
    int m, x, y, op, i;
    fin >> n >> m;
    for (i = 0; i < n; i++) {
        fin >> T[i + n];
    }
    Build();
    while (m--) {
        fin >> op >> x >> y;
        if (op == 1) {
            Update(x, y);
        } else {
            fout << Query(x, y) << "\n";
        }
    }
    f.close();
    fout.close();
    return 0;
}