#include <fstream>
#include <algorithm>
using namespace std;
ifstream f("arbint.in");
ofstream g("arbint.out");
int n,m,i,x[1000005],poz,uj,k,Max,a,b,tip;
int update(int csp, int left, int right)
{
    if (left == right)
    {
        x[csp] = uj;
        return 0;
    }
    int k = (left+right)/2;
    if (poz <= k) update(2*csp, left, k);
    else          update(2*csp+1, k+1, right);
    x[csp] = max(x[2*csp], x[2*csp+1]);
}
int query(int csp, int left, int right)
{
    if (a<=left && right<=b)
    {
        if (Max < x[csp]) Max = x[csp];
        return 0;
    }
    int k = (left+right)/2;
    if (a <= k) query(2*csp, left, k);
    if (k < b)  query(2*csp+1, k+1, right);
}
int main()
{
    f >> n >> m;
    for (i=1; i<=n; i++)
    {
        f >> uj;
        poz = i;
        update(1,1,n);
    }
    for (i=1; i<=m; i++)
    {
        f >> tip >> a >> b;
        if (tip)
        {
            poz = a;
            uj = b;
            update(1,1,n);
        }
        else
        {
            Max = -1;
            query(1,1,n);
            g << Max << "\n";
        }
    }
}