#include <fstream>
using namespace std;

ifstream in ("arbint.in");
ofstream out("arbint.out");
const int maxn = 100001;

int arb[4*maxn+66];
int val, x, pos, start, end, maxim;

inline int max(int a, int b)
{
    if (a < b) return b;
    else return a;
}

void update(int nod, int a, int b)
{
    if (a == b)
    {
        arb[nod] = val;
        return;
    }
    int mid = (a + b) / 2;
    if (pos <= mid) update(2*nod, a, mid);
    else            update(2*nod+1, mid+1, b);
    arb[nod] = max(arb[2*nod], arb[2*nod+1]);
}

void query(int nod, int a, int b)
{
    if (start <= a && b <= end)
    {
        if (maxim < arb[nod]) maxim = arb[nod];
        return;
    }
    int mid = (a + b) / 2;
    if (start <= mid) query(2*nod, a, mid);
    if (mid < end) query(2*nod+1, mid+1, b);
}

int main()
{
    int n, m, x, a, b;
    in >> n >> m;
    for (int i = 1; i <= n; i++)
    {
        in >> x;
        pos = i; val = x;
        update(1, 1, n);
    }
    for (int i = 1; i <= m; i++)
    {
        in >> x >> a >> b;
        if (x == 0)
        {
            maxim = -1;
            start = a; end = b;
            query(1, 1, n);
            out << maxim << '\n';
        }
        else
        {
            pos = a; val = b;
            update(1, 1, n);
        }
    }
    return 0;
}