#include <iostream>
#include <fstream>
#include <algorithm>
using namespace std;
ifstream f("arbint.in");
ofstream g("arbint.out");
int N, M, m;
int ArbInt[4 * 100001 + 66];
void Update(int nod, int left, int right, int Pos, int Val)
{
if (left == right)
{
ArbInt[nod] = Val;
return;
}
int mij = (left + right) / 2;
if (Pos <= mij)
Update(2 * nod, left, mij, Pos, Val);
else
Update(2 * nod + 1, mij + 1, right, Pos, Val);
ArbInt[nod] = max(ArbInt[2 * nod], ArbInt[2 * nod + 1]);
}
void Query(int nod, int left, int right, int start, int finish)
{
if (start <= left && right <= finish)
{
if (m < ArbInt[nod])
m = ArbInt[nod];
return;
}
int mij = (left + right) / 2;
if (start <= mij) Query(2 * nod, left, mij, start, finish);
if (mij < finish) Query(2 * nod + 1, mij + 1, right, start, finish);
}
int main()
{
int X, A, B;
f >> N >> M;
for (int i = 1; i <= N; i++)
{
f >> X; //citim valoarea
Update(1, 1, N, i, X);
}
for (int i = 1; i <= M; i++)
{
f >> X >> A >> B; //citim operatia si valorile
if (X == 0) //daca operatia e 0 trebuie sa cautam elementul maxim din intervalul [A,B]
{
m = -1;
Query(1, 1, N, A, B);
g << m << "\n";
}
else //daca operatia e 1 trebuie sa schimbam valoarea de la indexul A cu valoarea de la indexul B
{
Update(1, 1, N, A, B);
}
}
}