Submission #235905

#	Time	Username	Problem	Language	Result	Execution time	Memory
235905		dlwocks31	Split the sequence (APIO14_sequence)	C++17	100 / 100	394 ms	84216 KiB

sequence

#include <bits/stdc++.h>
#define MAXN 100005
using namespace std;
typedef long long ll;
typedef pair<ll,int> pli;
typedef vector<int> vi;
 
typedef struct CHT{
    ll la[MAXN], lb[MAXN]; int lz[MAXN];
    int stkn=0,pt=1;
    void insert(ll a, ll b, int z){
        while(stkn>pt){
            if(a==la[stkn] && b>=lb[stkn]) stkn--;
            else if((lb[stkn]-b)*(la[stkn]-la[stkn-1])<(a-la[stkn])*(lb[stkn-1]-lb[stkn])) stkn--;
            else break;
        }
        if(a==la[stkn] && b>=lb[stkn] && z!=0)
            return;
        la[++stkn]=a;
        lb[stkn]=b;
        lz[stkn]=z;
    }
    pli query(ll x){
        while(pt<stkn && (lb[pt]-lb[pt+1])<(la[pt+1]-la[pt])*x) pt++;
        return make_pair(la[pt]*x+lb[pt],lz[pt]);
    }
}CHT;
 
ll a[MAXN],D[2][MAXN],S[MAXN];
int pre[205][MAXN];
 
int main(){
    int n,k;
    scanf("%d %d",&n,&k);
    for(int i=1;i<=n;i++) scanf("%lld",&a[i]), S[i]=S[i-1]+a[i];
    for(int i=1;i<=k;i++){
        CHT c; c.insert(0,0,0);
        for(int j=1;j<=n;j++){
            pli temp=c.query(S[j]);
            D[i%2][j]=temp.first;
            pre[i][j]=temp.second;
            c.insert(S[j],D[(i-1)%2][j]-S[j]*S[j],j);
        }
    }
    printf("%lld\n",D[k%2][n]);
    int here=n;
    vi ans;
    ans.push_back(-1);
    for(int i=1;i<=k;i++){
        ans.push_back(pre[k-i+1][here]);
        here=pre[k-i+1][here];
    }
    sort(ans.begin(),ans.end());
    for(int i=1;i<=k;i++){
        if(ans[i]==0) ans[i]=1;
        if(ans[i]<=ans[i-1]) ans[i]=ans[i-1]+1;
        printf("%d ",ans[i]);
    }
    return 0;
}
 

Compilation message (stderr)

sequence.cpp: In function 'int main()':
sequence.cpp:34:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
     scanf("%d %d",&n,&k);
     ~~~~~^~~~~~~~~~~~~~~
sequence.cpp:35:46: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
     for(int i=1;i<=n;i++) scanf("%lld",&a[i]), S[i]=S[i-1]+a[i];
                           ~~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~

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