| # | 제출 시각 | 아이디 | 문제 | 언어 | 결과 | 실행 시간 | 메모리 |
|---|---|---|---|---|---|---|---|
| 971084 | 2024-04-27T23:16:57 Z | Unforgettablepl | 수열 (APIO14_sequence) | C++17 | 0 ms | 0 KB |
#include <bits/stdc++.h>
using namespace std;
#define int long long
struct fraction {
int n,d;
fraction(int n,int d):n(n),d(d){}
bool operator<(const fraction &other) const {
return __int128(n)*__int128(other.d)<__int128(other.n)*__int128(d);
}
};
struct line {
int m,k,idx_1,idx_2;
line(int m,int k):m(m),k(k),idx_1(idx_1),idx_2(idx_2){}
int operator()(int x) {
return m*x+k;
}
};
fraction getIntersect(line a,line b) {
return {a.k - b.k,b.m - a.m};
}
void addline(deque<line> &hull, line x) {
while(hull.size()>1 and getIntersect(hull[hull.size()-2],x)<getIntersect(hull[hull.size()-2],hull.back()))hull.pop_back();
hull.emplace_back(x);
}
tuple<int,int,int> get(deque<line> &hull, int x){
while(hull.size()>=2 and hull.front()(x)<=hull[1](x))hull.pop_front();
return {hull.front()(x),hull.front().idx_1,hull.front().idx_2};
}
int DP[100001][202];
pair<int,int> back[100001][202];
deque<line> hulls[202];
int P[100001];
int32_t main(){
ios_base::sync_with_stdio(false);
cin.tie(nullptr);
int n,k;
cin >> n >> k;k++;
for(int i=1;i<=n;i++)cin>>P[i];
for(int i=1;i<=n;i++)P[i]+=P[i-1];
for(int i=0;i<=k;i++)addline(hulls[i],{0,0,0,0});
for(int i=1;i<=n;i++){
for(int j=k;j;j--){
if(j!=1){for(int x=i-1;x;x--){
if(DP[i][j]<P[i]*P[x]-P[x]*P[x]+DP[x][j-1]){
DP[i][j] = P[i]*P[x]-P[x]*P[x]+DP[x][j-1];
back[i][j] = {x,j-1};
}
}}
auto [ans,last1,last2] = get(hulls[j-1],P[i]);
if(DP[i][j] != ans)
{
cout << ":DFSAOUIHfaspodi8uhjfg";
}
back[i][j] = {last1,last2};
addline(hulls[j],{P[i],DP[i][j]-P[i]*P[i],i,j});
}
}
cout << DP[n][k] << '\n';
vector<int> ans;
auto [curr1,curr2] = back[n][k];
while(curr1 and curr2){
ans.emplace_back(curr1);
auto [c1,c2] = back[curr1][curr2];curr1=c1;curr2=c2;
}
for(int&i:ans)cout<<i<<' ';
cout << '\n';
}