| # | Time | Username | Problem | Language | Result | Execution time | Memory | 
|---|---|---|---|---|---|---|---|
| 73905 | duckmoon99 | Homecoming (BOI18_homecoming) | C++14 | 0 ms | 0 KiB | 
This submission is migrated from previous version of oj.uz, which used different machine for grading. This submission may have different result if resubmitted.
#include "homecoming.h"
#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
using namespace std;
using namespace __gnu_pbds;
#define fi first
#define se second
#define mp make_pair
#define pb push_back
#define fbo find_by_order
#define ook order_of_key
#define INF 1e18
#define ret return
typedef long long ll;
typedef pair<int,int> ii;
typedef vector<int> vi;
typedef vector < pair<int, int> > vii;
typedef long double ld;
typedef tree<pair<int,int>, null_type, less<pair<int,int> >, rb_tree_tag, tree_order_statistics_node_update> pbds;
typedef set<int>::iterator sit;
typedef map<int,int>::iterator mit;
typedef vector<int>::iterator vit;
ll solve(int n, int k, int *A, int *B){
	ll tA = 0;
	ll tB = 0;
	for(int i = 0; i < n; i++){
		tA+=A[i];
		tB+=B[i];
	}
	ll anss = max(ll(0),tA-tB);
	if(k==1){
		ll ans = 0;
		for(int i = 0; i < n; i++){
			ans+=max(0,A[i]-B[i]);
		}
		ret ans;
	}
	int N = n;
	for(int T = 0; T < N; T++){
		//cout << "**" << t << endl;
		//banning the t-th book
		vi a, b;
		for(int i = 1; i < N; i++){
			a.pb(A[(i+t)%N]);
			b.pb(B[(i+t)%N]);
		}
		n=a.size();
		ll dp[n][k+5];
		ll cost[n];
		cost[0]=b[0];
		for(int i = 1; i < n; i++){
			cost[i]=b[i]+cost[i-1];
		}
		for(int i = n-1; i > n-k; i--){
			for(int j = k; j >= 0; j--){
				if(i+j-1>=n){
					dp[i][j]=-INF;
				}
				else{
					ll t = cost[i+j-1];
					if(i>=1)t-=cost[i-1];
					dp[i][j]=max(dp[i][j+1],-t+dp[i+j][0]);
				}
				//cout << i << " " << j << " " << dp[i][j] << endl;
			}
		}
		for(int i = n-k; i >= 0; i--){
			for(int j = k; j >= 0; j--){
				if(j==k){
					//cout << ",";
					dp[i][j]=a[i]-b[i]+dp[i+1][j-1];
				}
				else{
					ll t = cost[i+j-1];
					if(i>=1)t-=cost[i-1];
					dp[i][j]=-t;
					dp[i][j]=max(dp[i][j+1],-t+dp[i+j][0]);
				}
				//cout << i << " " << j << " " << dp[i][j] << endl;
			}
		}
		anss=max(dp[0][0],anss);
	}
	ret anss;
}
int main(){
	int n, k;
	cin >> n >> k;
	int a[n],b[n];
	for(int i = 0; i < n; i++){
		cin >> a[i];
	}
	for(int i = 0; i < n; i++){
		cin >> b[i];
	}
	cout << solve(n,k,a,b);
}
