//Original Code:
//#include <self/utility>
//#include <self/debug>
//using namespace std;
//int n;
//int a[200005],b[200005];
//ll res;
//int tr[200005];
//int ma[200005],mb[200005];
//
//ll calc(int x,int y)
//{
// return 1LL*min(ma[x],ma[y])*min(mb[x],mb[y])*(y-x+1);
//}
//
//void cdq1(int l,int r,int ql,int qr)
//{
// if(l==r) return;
// int md=l+r>>1;
// ll res=-inf;
// for(int i=ql;i<qr;i++)
// {
// ll v=calc(md,i);
// if(v>=res)
// {
// res=v;
// tr[md]=i;
// }
// }
// chmax(::res,res);
// cdq1(l,md,ql,tr[md]+1);
// cdq1(md+1,r,tr[md],qr);
//}
//
//void cdq2(int l,int r,int ql,int qr)
//{
// if(l==r) return;
// int md=l+r>>1;
// ll res=-inf;
// for(int i=ql;i<qr;i++)
// {
// ll v=calc(md,i);
// if(v>=res)
// {
// res=v;
// tr[md]=i;
// }
// }
// chmax(::res,res);
// cdq2(l,md,r,tr[md],qr);
// cdq2(md+1,ql,tr[md]+1);
//}
//
//void solve(int l,int r)
//{
// if(r-l==1)
// {
// chmax(res,1LL*a[l]*b[l]);
// return;
// }
// int md=l+r>>1;
// for(int i=md-1;i>=l;i--)
// {
// ma[i]=min(i==md-1?inf:ma[i+1],a[i]);
// mb[i]=min(i==md-1?inf:mb[i+1],b[i]);
// }
// for(int i=md;i<r;i++)
// {
// ma[i]=min(i==md?inf:ma[i-1],a[i]);
// mb[i]=min(i==md?inf:mb[i-1],b[i]);
// }
// cdq1(l,md,md,r);
// cdq2(l,md,md,r);
// solve(l,md);
// solve(md,r);
//}
//
//int main()
//{
// // freopen("input.txt","r",stdin);
// cin>>n;
// for(int i=0;i<n;i++) scanf("%d%d",a+i,b+i);
// solve(0,n);
// cout<<res<<endl;
// return 0;
//}
//substituted with C++ Inliner
#ifndef _SELF_UTILITY
#define _SELF_UTILITY 1
#include <numeric>
#include <iostream>
#include <algorithm>
#include <cmath>
#include <stdio.h>
#include <stdlib.h>
#include <vector>
#include <map>
#include <queue>
#include <set>
#include <string>
#include <string.h>
#include <stack>
#include <assert.h>
#include <bitset>
#include <time.h>
#define Endl endl
#define mp make_pair
#define mt make_tuple
#define ll long long
#define ull unsigned long long
#define pii pair<int,int>
#define over(A) {cout<<A<<endl;exit(0);}
#define all(A) A.begin(),A.end()
#define quickcin ios_base::sync_with_stdio(false);
#ifdef __TAKE_MOD
int mod;
#else
#ifdef __TAKE_CONST_MOD
const int mod=__TAKE_CONST_MOD;
#else
const int mod=1000000007;
#endif
#endif
const int gmod=3;
const int inf=1039074182;
#ifdef __TAKE_CONST_EPS
const double eps=__TAKE_CONST_EPS;
#else
const double eps=1e-9;
#endif
const double pi=3.141592653589793238462643383279;
const ll llinf=2LL*inf*inf;
template <typename T1,typename T2> inline void chmin(T1 &x,T2 b) {if(b<x) x=b;}
template <typename T1,typename T2> inline void chmax(T1 &x,T2 b) {if(b>x) x=b;}
inline void chadd(int &x,int b) {x+=b-mod;x+=(x>>31 & mod);}
template <typename T1,typename T2> inline void chadd(T1 &x,T2 b) {x+=b;if(x>=mod) x-=mod;}
template <typename T1,typename T2> inline void chmul(T1 &x,T2 b) {x=1LL*x*b%mod;}
template <typename T1,typename T2> inline void chmod(T1 &x,T2 b) {x%=b,x+=b;if(x>=b) x-=b;}
template <typename T> inline T mabs(T x) {return (x<0?-x:x);}
using namespace std;
#endif
#ifndef _SELF_DEBUG
#define _SELF_DEBUG 1
#ifndef _SELF_OPERATOR
#define _SELF_OPERATOR 1
using namespace std;
template <typename T>
ostream & operator<<(ostream &cout, const vector<T> &vec)
{
cout << "{";
for (int i = 0; i < (int)vec.size(); i++)
{
cout << vec[i];
if (i != (int)vec.size() - 1)
cout << ',';
}
cout << "}";
return cout;
}
template <typename T1, typename T2>
ostream &operator<<(ostream &cout, pair<T1, T2> p)
{
cout << "(" << p.first << ',' << p.second << ")";
return cout;
}
template <typename T, typename T2>
ostream &operator<<(ostream &cout, set<T, T2> s)
{
vector<T> t;
for (auto x : s)
t.push_back(x);
cout << t;
return cout;
}
template <typename T, typename T2>
ostream &operator<<(ostream &cout, multiset<T, T2> s)
{
vector<T> t;
for (auto x : s)
t.push_back(x);
cout << t;
return cout;
}
template <typename T>
ostream &operator<<(ostream &cout, queue<T> q)
{
vector<T> t;
while (q.size())
{
t.push_back(q.front());
q.pop();
}
cout << t;
return cout;
}
template <typename T1, typename T2, typename T3>
ostream &operator<<(ostream &cout, map<T1, T2, T3> m)
{
for (auto &x : m)
{
cout << "Key: " << x.first << ' ' << "Value: " << x.second << endl;
}
return cout;
}
template <typename T1, typename T2>
void operator+=(pair<T1, T2> &x,const pair<T1, T2> y)
{
x.first += y.first;
x.second += y.second;
}
template <typename T1,typename T2>
pair<T1,T2> operator + (const pair<T1,T2> &x,const pair<T1,T2> &y)
{
return make_pair(x.first+y.first,x.second+y.second);
}
template <typename T1,typename T2>
pair<T1,T2> operator - (const pair<T1,T2> &x,const pair<T1,T2> &y)
{
return mp(x.first-y.first,x.second-y.second);
}
template <typename T1, typename T2>
pair<T1, T2> operator-(pair<T1, T2> x)
{
return make_pair(-x.first, -x.second);
}
template <typename T>
vector<vector<T>> operator~(vector<vector<T>> vec)
{
vector<vector<T>> v;
int n = vec.size(), m = vec[0].size();
v.resize(m);
for (int i = 0; i < m; i++)
{
v[i].resize(n);
}
for (int i = 0; i < m; i++)
{
for (int j = 0; j < n; j++)
{
v[i][j] = vec[j][i];
}
}
return v;
}
#endif
#include <sstream>
void print0x(int x)
{
std::vector <int> vec;
while(x)
{
vec.push_back(x&1);
x>>=1;
}
std::reverse(vec.begin(),vec.end());
for(int i=0;i<(int)vec.size();i++)
{
std::cout<<vec[i];
}
std::cout<<' ';
}
template <typename T>
void print0x(T x,int len)
{
std::vector <int> vec;
while(x)
{
std::cout<<(x&1);
x>>=1;
len--;
// vec.push_back(x&1);
// x>>=1;
}
while(len--) cout<<0;
// reverse(vec.begin(),vec.end());
// for(int i=(int)vec.size();i<len;i++)
// {
// putchar('0');
// }
// for(size_t i=0;i<vec.size();i++)
// {
// std::cout<<vec[i];
// }
// std::cout<<' ';
}
vector<string> vec_splitter(string s) {
s += ',';
vector<string> res;
while(!s.empty()) {
res.push_back(s.substr(0, s.find(',')));
s = s.substr(s.find(',') + 1);
}
return res;
}
void debug_out(
vector<string> __attribute__ ((unused)) args,
__attribute__ ((unused)) int idx,
__attribute__ ((unused)) int LINE_NUM) { cerr << endl; }
template <typename Head, typename... Tail>
void debug_out(vector<string> args, int idx, int LINE_NUM, Head H, Tail... T) {
if(idx > 0) cerr << ", "; else cerr << "Line(" << LINE_NUM << ") ";
stringstream ss; ss << H;
cerr << args[idx] << " = " << ss.str();
debug_out(args, idx + 1, LINE_NUM, T...);
}
#define debug(...) debug_out(vec_splitter(#__VA_ARGS__), 0, __LINE__, __VA_ARGS__)
#endif
using namespace std;
int n;
int a[200005],b[200005];
ll res;
int tr[200005];
int ma[200005],mb[200005];
ll calc(int x,int y)
{
return 1LL*min(ma[x],ma[y])*min(mb[x],mb[y])*(y-x+1);
}
void cdq1(int l,int r,int ql,int qr)
{
if(l==r) return;
int md=l+r>>1;
ll res=-inf;
for(int i=ql;i<qr;i++)
{
ll v=calc(md,i);
if(v>=res)
{
res=v;
tr[md]=i;
}
}
chmax(::res,res);
cdq1(l,md,ql,tr[md]+1);
cdq1(md+1,r,tr[md],qr);
}
void cdq2(int l,int r,int ql,int qr)
{
if(l==r) return;
int md=l+r>>1;
ll res=-inf;
for(int i=ql;i<qr;i++)
{
ll v=calc(md,i);
if(v>=res)
{
res=v;
tr[md]=i;
}
}
chmax(::res,res);
cdq2(l,md,r,tr[md],qr);
cdq2(md+1,ql,tr[md]+1);
}
void solve(int l,int r)
{
if(r-l==1)
{
chmax(res,1LL*a[l]*b[l]);
return;
}
int md=l+r>>1;
for(int i=md-1;i>=l;i--)
{
ma[i]=min(i==md-1?inf:ma[i+1],a[i]);
mb[i]=min(i==md-1?inf:mb[i+1],b[i]);
}
for(int i=md;i<r;i++)
{
ma[i]=min(i==md?inf:ma[i-1],a[i]);
mb[i]=min(i==md?inf:mb[i-1],b[i]);
}
cdq1(l,md,md,r);
cdq2(l,md,md,r);
solve(l,md);
solve(md,r);
}
int main()
{
// // freopen("input.txt","r",stdin);
cin>>n;
for(int i=0;i<n;i++) scanf("%d%d",a+i,b+i);
solve(0,n);
cout<<res<<endl;
return 0;
}
Compilation message
histogram.cpp: In function 'void cdq1(int, int, int, int)':
histogram.cpp:334:10: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
334 | int md=l+r>>1;
| ~^~
histogram.cpp: In function 'void cdq2(int, int, int, int)':
histogram.cpp:353:10: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
353 | int md=l+r>>1;
| ~^~
histogram.cpp:365:23: error: too many arguments to function 'void cdq2(int, int, int, int)'
365 | cdq2(l,md,r,tr[md],qr);
| ^
histogram.cpp:350:6: note: declared here
350 | void cdq2(int l,int r,int ql,int qr)
| ^~~~
histogram.cpp:366:23: error: too few arguments to function 'void cdq2(int, int, int, int)'
366 | cdq2(md+1,ql,tr[md]+1);
| ^
histogram.cpp:350:6: note: declared here
350 | void cdq2(int l,int r,int ql,int qr)
| ^~~~
histogram.cpp: In function 'void solve(int, int)':
histogram.cpp:376:10: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
376 | int md=l+r>>1;
| ~^~
histogram.cpp: In function 'int main()':
histogram.cpp:397:28: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
397 | for(int i=0;i<n;i++) scanf("%d%d",a+i,b+i);
| ~~~~~^~~~~~~~~~~~~~~~
