#include <stdio.h>
#include <fstream>
#include <assert.h>
using namespace std;
int n, m, MaxArb[4*100001+66], start, finish, Val, Pos, maxim;

void Update(int nod, int left, int right)
{
    if (left == right)
    {
        MaxArb[nod] = Val;
        return;
    }
    int div = (left + right) / 2;
    if (Pos <= div)
        Update(2 * nod, left, div);
    else
        Update(2 * nod + 1, div + 1, right);

    if(MaxArb[2 * nod] > MaxArb[2 * nod + 1])
        MaxArb[nod] = MaxArb[2 * nod];
    else MaxArb[nod] = MaxArb[2 * nod + 1];
}

void Query(int nod, int left, int right)
{
    if (start <= left && right <= finish)
    {
        if (maxim < MaxArb[nod])
            maxim = MaxArb[nod];
        return;
    }

    int div = (left + right) / 2;
    if ( start <= div ) Query(2 * nod, left, div);
    if ( div < finish ) Query(2 * nod + 1, div + 1, right);
}

int main()
{
    int x, a, b;
    freopen("arbint.in", "r", stdin);
    freopen("arbint.out", "w", stdout);

    scanf("%d%d", &n, &m);
    for (int i = 1; i <= n; i++)
    {
        scanf("%d", &x);
        Pos = i, Val = x;
        Update(1, 1, n);
    }

    for (int i = 1; i <= m; i++)
    {
        scanf("%d%d%d", &x, &a, &b);
        if ( x == 0 )
        {
            maxim = -1;
            start = a, finish = b;
            Query(1,1,n);
            printf("%d\n", maxim);
        }
        else
        {
            Pos = a, Val = b;
            Update(1, 1, n);
        }
    }
    return 0;
}