#include <bits/stdc++.h>

using namespace std;

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

int n, m, baza, tree[270000];

void update(int poz, int val)
{
    poz+=baza - 1;
    tree[poz] = val;

    poz/=2;

    for(; poz; poz/=2)
        tree[poz] = max(tree[poz*2], tree[poz*2 + 1]);

}

int maxim(int a, int b)
{
    a+=baza - 1;
    b+=baza - 1;
    int maxim = 0;

    for(; a<=b; a/=2, b/=2)
    {
        if(a % 2 == 1)
            maxim = max(maxim, tree[a]), a++;

        if(b%2 == 0)
            maxim = max(maxim, tree[b]), b--;
    }
    return maxim;

}


int main()
{
    fin>>n>>m;

    baza = pow(2, (int)log2(n) + ( log2(n) > (int)log2(n) ? 1 : 0 )) + 0.5;

    for(int i = baza; i<= baza + n - 1; i++)
        fin>>tree[i];

    for(int k = baza/2; k; k/=2)
        for(int i = k; i <= k*2 - 1; i++)
            tree[i] = max(tree[i*2], tree[i*2 + 1]);

    for(int c, a, b, i = 1; i<=m; i++)
    {
        fin>>c>>a>>b;
        if(c == 1)
            update(a, b);
        else
            fout<<maxim(a, b)<<'\n';
    }


    return 0;
}