#include <fstream>

#define dim 100005

using namespace std;

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

int n, m;
int MaxArb[4 * dim + 70];
int start, finish, Val, Pos, maxx;

void Update(int nod, int st, int dr)
{
    if(st == dr)
    {
        MaxArb[nod] = Val;
        return;
    }

    int mid = (st + dr) / 2;
    if(Pos <= mid)
        Update(2 * nod, st, mid);
    else Update(2 * nod + 1, mid + 1, dr);

    MaxArb[nod] = max(MaxArb[2 * nod], MaxArb[2 * nod + 1]);
}

void Query(int nod, int st, int dr)
{
    if(start <= st && dr <= finish)
    {
        if(maxx < MaxArb[nod])
            maxx = MaxArb[nod];
		return; ///mama cat am stat sa imi dau seama ca e in afara if-ului de mai sus :))
    }

    int mid = (st + dr) / 2;
    if(start <= mid)
        Query(2 * nod, st, mid);
    if(mid < finish)
        Query(2 * nod + 1, mid + 1, dr);
}

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

    for(int i = 1; i <= n; ++i)
    {
        int x;
        fin >> x;

        Pos = i;
        Val = x;
        Update(1, 1, n);
    }

    for(int i = 1; i <= m; ++i)
    {
        int c, a, b;
        fin >> c >> a >> b;

        if(c == 0)
        {
            maxx = -1;
            start = a;
            finish = b;
            Query(1, 1, n);

            fout << maxx << '\n';
        }
        else
        {
            Pos = a;
            Val = b;
            Update(1, 1, n);
        }
    }
    return 0;
}