#include <bits/stdc++.h>
using namespace std;
#define Nmax 100010
 
int n;
int arb[262145];
 
void update(int, int, int, int, int) ;
int query(int, int, int, int, int) ;
 
int main()
{
	freopen("arbint.in", "r", stdin);
	freopen("arbint.out", "w", stdout);
	ios_base::sync_with_stdio(false);

    int i, q, a, b, tip;
    scanf("%d %d", &n, &q);
    for(i = 1; i <= n; ++i)
    {
        scanf("%d", &a);
        update(1, 1, n, i, a);
    }
    for(i = 0; i < q; ++i)
    {
        scanf("%d %d %d", &tip, &a, &b);
        if(tip == 0) printf("%d\n", query(1, 1, n, a, b));
        else update(1, 1, n, a, b);
    }
    return 0;
}
 
void update(int nod, int st, int dr, int poz, int val)
{
    if(st == dr)
    {
        arb[nod] = val;
        return;
    }
 
    int m = (st + dr) >> 1;
    if(poz <= m) update(2 * nod, st, m, poz, val);
    else update(2 * nod + 1, m + 1, dr, poz, val);
 
    arb[nod] = max(arb[2 * nod], arb[2 * nod + 1]);
}
 
int query(int nod, int st, int dr, int a, int b)
{
    if(a <= st && dr <= b) return arb[nod];
 
    int rez1 = -1, rez2 = -1, m = (st + dr) >> 1;
    if(a <= m) rez1 = query(2 * nod, st, m, a, b);
    if(b > m) rez2 = query(2 * nod + 1, m + 1, dr, a, b);
 
    return max(rez1, rez2);
}