#include <bits/stdc++.h>
using namespace std;
#define pb push_back
#define dbg(x) cout << #x <<": " << x << "\n";
#define sz(x) ((int)x.size())
using ll = long long;
const string fn = "file";
// ifstream fin(fn + ".in");
// ofstream fout(fn + ".out");
class InP {
FILE *fin;
char *buff;
int sp;
public:
InP(const char *c) {
fin = fopen(c, "r");
buff = new char[4096]();
sp = 4095;
}
char read_ch() {
sp++;
if (sp == 4096) {
fread(buff, 1, 4096, fin);
sp = 0;
}
return buff[sp];
}
InP& operator >> (int &n) {
char c;
while (!isdigit(c = read_ch()) && c != '-');
int sgn = 1;
if (c == '-') {
sgn = -1;
n = 0;
}
else {
n = c - '0';
}
while (isdigit(c = read_ch()))
n = n * 10 + c - '0';
n = n * sgn;
return *this;
}
};
InP fin("arbint.in");
class OutP {
FILE *fout;
char *buff;
int sp;
public:
OutP(const char *c) {
fout = fopen(c, "w");
buff = new char[50000]();
sp = 0;
}
~OutP() {
fwrite(buff, 1, sp, fout);
fclose(fout);
}
void write_ch(char c) {
if (sp == 50000) {
fwrite(buff, 1, sp, fout);
sp = 0;
}
buff[sp++] = c;
}
OutP& operator <<(int n) {
if (n <= 9) {
write_ch(n + '0');
}
else {
(*this) << (n / 10);
write_ch(n % 10 + '0');
}
return *this;
}
OutP& operator <<(char c) {
write_ch(c);
return (*this);
}
OutP& operator <<(char *c) {
while (*c) {
write_ch(*c);
c++;
}
return (*this);
}
};
OutP fout("arbint.out");
int n, m;
int a[400005];
void build(int nod, int st, int dr) {
if (st == dr) {
fin >> a[nod];
} else {
int mid = (st + dr) >> 1;
build(nod << 1, st, mid);
build(nod << 1 | 1, mid + 1, dr);
a[nod] = max(a[nod << 1], a[nod << 1 | 1]);
}
}
void upd(int nod, int st, int dr, int p, int x) {
if (st == dr) {
a[nod] = x;
}
else {
int mid = (st + dr) >> 1;
if (p <= mid)
upd(nod << 1, st, mid, p, x);
else upd(nod << 1 | 1, mid + 1, dr, p, x);
a[nod] = max(a[nod << 1], a[nod << 1 | 1]);
}
}
int qry(int nod, int st, int dr, int x, int y) {
if (st > dr || st > y || dr < x)
return -1;
if (st >= x && dr <= y)
return a[nod];
int mid = (st + dr) >> 1;
int q1 = qry(nod << 1, st, mid, x, y);
int q2 = qry(nod << 1 | 1, mid + 1, dr, x, y);
return max(q1, q2);
}
int main() {
fin >> n >> m;
build(1, 1, n);
while (m--) {
int op, x, y;
fin >> op >> x >> y;
if (op == 0)
fout << qry(1, 1, n, x, y) << '\n';
else upd(1, 1, n, x, y);
}
return 0;
}