Submission #1008030

#	Time	Username	Problem	Language	Result	Execution time	Memory
1008030		Mardonbekhazratov	Boxes with souvenirs (IOI15_boxes)	C++17	20 / 100	0 ms	348 KiB

boxes

#include "boxes.h"
#include<bits/stdc++.h>
#define ll long long
using namespace std;

const ll INFLL=1e18;

long long delivery(int N, int K, int L, int p[]) {
    if(K==1){
        ll ans=0;
        for(int i=0;i<N;i++) ans+=min(p[i],L-p[i])*2;
        return ans;
    }
    if(K==N){
        ll ans=L;
        for(int i=0;i<N;i++){
            ans=min(ans,2ll*p[i-1]+(L-p[i])*2);
        }
        ans=min(ans,2LL*min({L-p[0],p[N-1]}));
        return ans;
    }
    vector<ll>pref(N+1),suff(N+2);
    pref[0]=suff[N+1]=0;
    ll sl=0,sr=0;
    for(int i=0;i<N;i++){
        pref[i+1]=2*p[i];
        suff[N-i]=2*(L-p[N-i-1]);
        if(i>=K) pref[i+1]+=pref[i-K+1],suff[N-i]+=suff[N-i+K];
    }
    ll ans=INFLL;
    for(int i=1;i<=N+1;i++){
        ans=min(ans,pref[i-1]+suff[i]);
    }
    return ans;
}

Compilation message (stderr)

boxes.cpp: In function 'long long int delivery(int, int, int, int*)':
boxes.cpp:24:8: warning: unused variable 'sl' [-Wunused-variable]
   24 |     ll sl=0,sr=0;
      |        ^~
boxes.cpp:24:13: warning: unused variable 'sr' [-Wunused-variable]
   24 |     ll sl=0,sr=0;
      |             ^~

• Subtask 1: 10 / 10
• Subtask 2: 10 / 10
• Subtask 3: 0 / 15
• Subtask 4: 0 / 15
• Subtask 5: 0 / 20
• Subtask 6: 0 / 30