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#include <fstream>
#include <vector>
#include <cmath>
using namespace std;
ifstream fin ("arbint.in");
ofstream fout ("arbint.out");
vector <int> aint;
int rightmax, n;
const int NMAX = 1e5;
int v[NMAX + 5];
void Allocate()
{
int exp = log2(n);
if((1 << exp) != n)
exp++;
aint.resize(2 * (1 << exp) + 5);
rightmax = 1 << exp;
}
void build(int node = 1, int left = 1, int right = rightmax)
{
if(left == right and left > n)
{
aint[node] = 0;
return;
}
if(left == right)
{
aint[node] = v[left];
return;
}
int mid = (left + right) / 2;
build(2 * node, left, mid);
build(2 * node + 1, mid + 1, right);
aint[node] = max(aint[2 * node], aint[2 * node + 1]);
}
void update(int pos, int value, int node = 1, int left = 1, int right = rightmax)
{
if(left == right and left > n)
{
aint[node] = 0;
return;
}
if(left == right)
{
aint[node] = value;
return;
}
int mid = (left + right) / 2;
if(pos <= mid)
update(pos, value, 2 * node, left, mid);
if(pos > mid)
update(pos, value, 2 * node + 1, mid + 1, right);
aint[node] = max(aint[2 * node], aint[2 * node + 1]);
}
int query(int qleft, int qright, int node = 1, int left = 1, int right = rightmax)
{
if(qleft <= left and right <= qright)
return aint[node];
int mid = (left + right) / 2, leftans = 0, rightans = 0;
if(qleft <= mid)
leftans = query(qleft, qright, 2 * node, left, mid);
if(mid < qright)
rightans = query(qleft, qright, 2 * node + 1, mid + 1, right);
return max(leftans, rightans);
}
int main()
{
int m;
fin >> n >> m;
Allocate();
for(int i = 1; i <= n; i++)
fin >> v[i];
build();
for(int i = 1; i <= m; i++)
{
int op, x, y;
fin >> op >> x >> y;
if(op == 0)
fout << query(x, y) << '\n';
else if(op == 1)
update(x, y);
}
fin.close();
fout.close();
return 0;
}