#include <bits/stdc++.h>
using namespace std;
const int NMAX = 2e5;
long long det(pair<int,int> a,pair<int,int> b,pair<int,int> c) {
return 1LL * a.first * (b.second - c.second) + 1LL * b.first * (c.second - a.second) + 1LL * c.first * (a.second - b.second);
}
bool cmp(pair<int,int> a,pair<int,int> b) {
return det(make_pair(0,0),a,b) > 0;
}
struct node_t {
int lst_ind;
vector<pair<long long,long long> > points;
node_t operator + (const node_t &other)const {
node_t ans;
for(auto it:points) {
ans.points.push_back(it);
}
for(auto it:other.points) {
ans.points.push_back(it);
}
sort(ans.points.begin(),ans.points.end(),cmp);
vector<pair<long long,long long> > tmp;
for(auto it:ans.points) {
while((int)tmp.size() >= 2 && det(tmp[(int)tmp.size() - 2],tmp[(int)tmp.size() - 1],it) < 0) {
tmp.pop_back();
}
tmp.push_back(it);
}
ans.points.swap(tmp);
ans.lst_ind = (int)ans.points.size() - 1;
return ans;
}
long long query(pair<long long,long long> v) {
/*while(lst_ind + 1 < (int)points.size() && points[lst_ind].first * v.first + points[lst_ind].second * v.second <= points[lst_ind + 1].first * v.first + points[lst_ind + 1].second * v.second) {
lst_ind++;
}*/
while(lst_ind - 1 >= 0 && points[lst_ind].first * v.first + points[lst_ind].second * v.second <= points[lst_ind - 1].first * v.first + points[lst_ind - 1].second * v.second) {
lst_ind--;
}
return points[lst_ind].first * v.first + points[lst_ind].second * v.second;
}
node_t() {
lst_ind = 0;
points = vector<pair<long long,long long> >();
}
};
class SegmentTree {
int n;
vector<node_t> aint;
void build(int nod,int st,int dr,vector<pair<long long,long long> > &v) {
if(st == dr) {
aint[nod].points = {v[st]};
return ;
}
int mid = (st + dr) / 2;
build(nod * 2,st,mid,v);
build(nod * 2 + 1,mid + 1,dr,v);
aint[nod] = aint[nod * 2] + aint[nod * 2 + 1];
}
long long query(int nod,int st,int dr,int l,int r,pair<long long,long long> v) {
if(dr < l || st > r) {
return 0;
}
if(l <= st && dr <= r) {
return aint[nod].query(v);
}
int mid = (st + dr) / 2;
return max(query(nod * 2,st,mid,l,r,v),query(nod * 2 + 1,mid + 1,dr,l,r,v));
}
public:
SegmentTree(int n,vector<pair<long long,long long> > v) {
this->n = n;
this->aint = vector<node_t>(4 * n + 5,node_t());
build(1,1,n,v);
}
long long query(int l,int r,pair<long long,long long> v) {
return query(1,1,n,l,r,v);
}
};
int n;
int a[NMAX + 5];
int b[NMAX + 5];
long long solve(int st,int dr) {
if(st == dr) {
return 1LL * a[st] * b[st];
}
int mid = (st + dr) / 2;
long long ans = max(solve(st,mid),solve(mid + 1,dr));
int mi_a = 1e9;
int mi_b = 1e9;
int i_a = mid;
int i_b = mid;
int i2_b = mid;
vector<pair<long long,long long> > points = {};
int mip_b = 1e9;
for(int i = mid; i >= st; i--) {
mip_b = min(mip_b,b[i]);
points.push_back({1LL * mip_b,1LL * mip_b * (1 - i)});
}
points.push_back({0LL,0LL});
reverse(points.begin(),points.end());
SegmentTree aint(mid - st + 1,points);
for(int i = mid + 1; i <= dr; i++) {
mi_a = min(mi_a,a[i]);
mi_b = min(mi_b,b[i]);
while(i_a >= st && a[i_a] >= mi_a) {
i_a--;
}
while(i_b >= st && b[i_b] > mi_b) {
i_b--;
}
while(i2_b >= st && b[i2_b] >= mi_b) {
i2_b--;
}
ans = max(ans,1LL * mi_a * mi_b * (i - max(i_a,i2_b)));
if(i_a + 1 <= i_b) {
ans = max(ans,aint.query(i_a + 1 - (st - 1),i_b - (st - 1),make_pair(1LL * mi_a * i,1LL * mi_a)));
}
///[i_a + 1,i_b]
}
return ans;
}
int main() {
scanf("%d",&n);
for(int i = 1; i <= n; i++) {
scanf("%d %d",&a[i],&b[i]);
}
long long ans = 0;
ans = max(ans,solve(1,n));
ans = max(ans,solve(1,n));
swap(a,b);
ans = max(ans,solve(1,n));
reverse(a + 1,a + 1 + n);
reverse(b + 1,b + 1 + n);
ans = max(ans,solve(1,n));
swap(a,b);
printf("%lld\n",ans);
return 0;
}
Compilation message
histogram.cpp: In function 'int main()':
histogram.cpp:161:10: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
161 | scanf("%d",&n);
| ~~~~~^~~~~~~~~
histogram.cpp:164:14: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
164 | scanf("%d %d",&a[i],&b[i]);
| ~~~~~^~~~~~~~~~~~~~~~~~~~~
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
20 ms |
2124 KB |
Output is correct |
| 2 |
Correct |
24 ms |
2260 KB |
Output is correct |
| 3 |
Correct |
22 ms |
2180 KB |
Output is correct |
| 4 |
Correct |
20 ms |
2244 KB |
Output is correct |
| 5 |
Correct |
19 ms |
2188 KB |
Output is correct |
| 6 |
Correct |
19 ms |
2208 KB |
Output is correct |
| 7 |
Correct |
17 ms |
2128 KB |
Output is correct |
| 8 |
Correct |
29 ms |
2180 KB |
Output is correct |
| 9 |
Correct |
32 ms |
2148 KB |
Output is correct |
| 10 |
Correct |
30 ms |
2252 KB |
Output is correct |
| 11 |
Correct |
2 ms |
1868 KB |
Output is correct |
| 12 |
Correct |
24 ms |
2192 KB |
Output is correct |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
20 ms |
2124 KB |
Output is correct |
| 2 |
Correct |
24 ms |
2260 KB |
Output is correct |
| 3 |
Correct |
22 ms |
2180 KB |
Output is correct |
| 4 |
Correct |
20 ms |
2244 KB |
Output is correct |
| 5 |
Correct |
19 ms |
2188 KB |
Output is correct |
| 6 |
Correct |
19 ms |
2208 KB |
Output is correct |
| 7 |
Correct |
17 ms |
2128 KB |
Output is correct |
| 8 |
Correct |
29 ms |
2180 KB |
Output is correct |
| 9 |
Correct |
32 ms |
2148 KB |
Output is correct |
| 10 |
Correct |
30 ms |
2252 KB |
Output is correct |
| 11 |
Correct |
2 ms |
1868 KB |
Output is correct |
| 12 |
Correct |
24 ms |
2192 KB |
Output is correct |
| 13 |
Execution timed out |
2599 ms |
52976 KB |
Time limit exceeded |
| 14 |
Halted |
0 ms |
0 KB |
- |
