#include <iostream>
#include <fstream>
#include <cstring>
#include <algorithm>
#include <deque>
#include <iomanip>
#include <queue>
#include <cmath>
#include <map>
#include <vector>
#include <bitset>
#include <unordered_map>
#include <set>
using namespace std;

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

int n, m;

map<pair<int, int>, pair<int, int>> parents;
map<pair<int, int>, vector<pair<int, int>>> graph;
map<pair<int, int>, int> cost;

void findParents(int left, int right) {
    if (left == right) {
        return;
    }
    parents[{left, (left + right) / 2}] = {left, right};
    parents[{(left + right) / 2 + 1, right}] = {left, right};
    graph[{left, right}].push_back({left, (left + right) / 2});
    graph[{left, right}].push_back({(left + right) / 2 + 1, right});
    findParents(left, (left + right) / 2);
    findParents((left + right) / 2 + 1, right);
}

void update(pair<int, int> currentNode) {
    while (currentNode.first && currentNode.second) {
        cost[currentNode] = max(cost[graph[currentNode].front()], cost[graph[currentNode].back()]);
        currentNode = parents[currentNode];
    }
}

void modifyPos(int left, int right, int number) {
    cost[{left, right}] = number;
}

int findMax(int left, int right, int a, int b) {
    if (a <= left && right <= b) {
        return cost[{left, right}];
    } else if (right < a || left > b) {
        return 0;
    }
    return max(findMax(left, (left + right) / 2, a, b), findMax((left + right) / 2 + 1, right, a, b));
}

int main() {
    fin >> n >> m;
    findParents(1, n);
    for (int i = 1; i <= n; ++i) {
        int number;
        fin >> number;
        modifyPos(i, i, number);
        update(parents[{i, i}]);
    }
    for (int i = 1; i <= m; ++i) {
        int op, a, b;
        fin >> op >> a >> b;
        if (op == 0) {
            fout << findMax(1, n, a, b) << '\n';
        } else {
            modifyPos(a, a, b);
            update(parents[{a, a}]);
        }
    }
    return 0;
}