Submission #1143902

#	Time	Username	Problem	Language	Result	Execution time	Memory
1143902		imarn	Split the sequence (APIO14_sequence)	C++20	100 / 100	959 ms	81548 KiB

sequence

#include<bits/stdc++.h>
#define f first
#define s second
#define ll long long
#define pb push_back
#define pii pair<int,int>
#define pll pair<ll,ll>
#define sz(x) (int)x.size()
using namespace std;
const int mxn=2e5+5;
ll a[mxn]{0};
ll dpf[mxn]{0},dps[mxn]{0};
int pr[202][mxn]{0};
int cur=1,n;
void solve(int l,int r,int opl,int opr){
    if(l>r)return;
    int m=(l+r)>>1;
    pll t={-1e16,-1e16};
    for(int i=opl;i<=min(m-1,opr);i++){
        t=max(t,{dpf[i]+(a[n]-a[m])*(a[m]-a[i]),i});
    }dps[m]=t.f;pr[cur][m]=t.s;
    if(l==r)return;
    solve(l,m-1,opl,t.s);
    solve(m+1,r,t.s,opr);
}
int main(){
    ios_base::sync_with_stdio(0);cin.tie(0);
    int k;cin>>n>>k;
    for(int i=1;i<=n;i++)cin>>a[i],a[i]+=a[i-1];
    for(int i=1;i<=n;i++)dpf[i]=(a[i])*(a[n]-a[i]);
    for(int i=2;i<=k;i++){
        solve(i,n,i-1,n);
        for(int j=1;j<=n;j++)dpf[j]=dps[j];
        cur++;
    }ll ans=-1,mem=-1;
    for(int i=1;i<=n;i++){
        if(dpf[i]>ans){
            ans=dpf[i];
            mem=i;
        }
    }
    cout<<ans<<'\n';stack<int>st;st.push(mem);
    for(int i=cur-1;i>=1;i--){
        st.push(pr[i][mem]);mem=pr[i][mem];
    }while(!st.empty()){
        cout<<st.top()<<' ';st.pop();
    }
}

• Subtask 1: 11 / 11
• Subtask 2: 11 / 11
• Subtask 3: 11 / 11
• Subtask 4: 17 / 17
• Subtask 5: 21 / 21
• Subtask 6: 29 / 29