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

using namespace std;

vector<int> vals, int_tree;

int construct_int_tree(int l, int r, int i){
    if(l==r){
        int_tree[i] = vals[l];
        return vals[l];
    }
    int mid = l+(r-l)/2;
    int_tree[i] = max(construct_int_tree(l, mid, i*2+1),construct_int_tree(mid+1, r, i*2+2));
    return int_tree[i];
}

int maxi(int l, int r, int qs, int qe, int i){
    if (qs <= l && qe >= r)
        return int_tree[i];

    if (r < qs || l > qe)
        return -2;

    int mid = l+(r-l)/2;
    return max(maxi(l, mid, qs, qe, 2*i+1), maxi(mid+1, r, qs, qe, 2*i+2));
}

int change_element(int l, int r, int i, int k, int val){
    if(l==r){
        if(l==k)
            int_tree[i] = val;
        return int_tree[i];
    }
    int mid = l+(r-l)/2;
    int_tree[i] = max(change_element(l, mid, i*2+1, k, val),change_element(mid+1, r, i*2+2, k, val));
    return int_tree[i];
}

int main() {
    ifstream fin("arbint.in");
    ofstream fout("arbint.out");
    int n, m, x;
    /// Read data
    fin>>n>>m;
    for(int i=0;i<n;++i){
        fin>>x;
        vals.push_back(x);
    }
    /// Resize and construct tree
    x = 2*static_cast<int>(pow(2, ceil(log2(n))) - 1);
    int_tree.resize(x);
    construct_int_tree(0, n-1, 0);
    /// Walk tree for every range
    int a, b, op;
    while(m--){
        fin>>op>>a>>b;
        if(op==0)
            fout<<maxi(0, n-1,a-1, b-1, 0)<<'\n';
        else
            change_element(0,n-1,0,a-1, b);
    }
    return 0;
}