Pagini recente » Cod sursa (job #3183545) | Cod sursa (job #1971672) | Cod sursa (job #2139366) | Cod sursa (job #340533) | Cod sursa (job #1863307)
#include <bits/stdc++.h>
using namespace std;
class ipfstream{
ifstream f;
char buf[(int)1e5], *p = buf, *ep = buf + sizeof(buf);
void adv(){
if(++p == ep) f.read(p=buf, sizeof(buf)); }
public:
ipfstream(const char * const str): f(str){
f.read(buf, sizeof(buf)); }
ipfstream& operator>>(int& rhs){
while(*p < '0') adv();
rhs = 0;
while(*p >= '0') rhs = 10 * rhs + *p - '0', adv();
return *this; } };
class arbint{
int n;
vector<int> buf;
public:
arbint(const vector<int>& vv): n(vv.size()), buf(2*n){
copy(begin(vv), end(vv), begin(buf)+n);
for(int i = n-1; i; --i) buf[i] = max(buf[2*i], buf[2*i+1]); }
void update(int poz, const int val){
buf[poz += n] = val;
for(poz /= 2; poz; poz /= 2)
buf[poz] = max(buf[2*poz], buf[2*poz+1]); }
int query(int st, int dr){
int r = 0;
for(st += n, dr += n+1; st < dr; st /= 2, dr /= 2){
if(st%2) r = max(r, buf[st++]);
if(dr%2) r = max(r, buf[--dr]); }
return r; } };
int main(){
ipfstream f("arbint.in");
ofstream g("arbint.out");
int n, m;
f >> n >> m;
vector<int> v(n);
for(auto& x : v) f >> x;
arbint arb(v);
for(int i = 0, t, a, b; i < m; ++i){
f >> t >> a >> b;
if(t == 0) g << arb.query(a-1, b-1) << '\n';
else arb.update(a-1, b); }
return 0; }