Submission #13778

#	Time	Username	Problem	Language	Result	Execution time	Memory
13778		comet	Split the sequence (APIO14_sequence)	C++98	100 / 100	1161 ms	85484 KiB

sequence

#include<cstdio>
#include<algorithm>
#include<deque>
using namespace std;
typedef long long ll;
typedef pair<ll,int> pp;
ll d[2][100010],s[100010],N,K;
int r[201][100001];
void f(int x,int y){
    if(x==1)return;
    f(x-1,r[x][y]);
    printf("%d ",(int)r[x][y]);
}
struct convex{
    deque<ll> a,b;
   deque<int>c;
    void init(){a.clear();b.clear();c.clear();}
    void push(ll n,ll m,int v){
        while(a.size()>1&&(b[b.size()-2]-b.back())*(n-a.back())>=(b.back()-m)*(a.back()-a[a.size()-2])){
            a.pop_back();
            b.pop_back();
            c.pop_back();
        }
        a.push_back(n);
        b.push_back(m);
        c.push_back(v);
    }
    pp query(ll x){
        while(!a.empty()&&(a[1]-a[0])*x>(b[0]-b[1])){
            a.pop_front();
            b.pop_front();
            c.pop_front();
        }
        return pp(a[0]*x+b[0],c[0]);
    }
};
int main(){
    scanf("%lld%lld",&N,&K);
    if(K==0)K++;
    for(int i=1;i<=N;i++){
        scanf("%lld",&s[i]);
        s[i]+=s[i-1];
    }
    convex* pre=new convex;
    convex* cur=new convex;
    pp ret;
    for(int i=1;i<=N;i++){
        d[1][i]=s[i]*(s[N]-s[i]);
        pre->push(s[i],d[1][i]-s[i]*s[N],i);
    }
    for(int g=2;g<=K+1;g++){
        for(int i=g;i<=N;i++){
            ret=pre->query(s[i]);
            d[g&1][i]=ret.first+(s[N]-s[i])*s[i];
            r[g][i]=ret.second;
            cur->push(s[i],d[g&1][i]-s[i]*s[N],i);
        }
        pre->init();
        swap(cur,pre);
    }
    printf("%lld\n",d[(K+1)&1][N]);
    f(K+1,N);
    delete cur,pre;
}

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