제출 #853027

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
853027		Benmath	Homecoming (BOI18_homecoming)	C++14	100 / 100	228 ms	188576 KiB

homecoming

#include<homecoming.h>
#include<bits/stdc++.h>
using namespace std;
long long int calculate (int i, int j, long long int prefiks[]){
    if(i == 0){
        return prefiks[j];
    }else{
        return prefiks[j] - prefiks[i-1];
    }
}
long long solve(int N, int K, int *A, int *B){
    int n = N;
    int k = K;
    long long int a[n];
    long long int b[n];
    long long int dp[n];
    long long int dp1[n];
    long long int sum1 = 0;
    long long int pref1[2*n+1];
    long long int pref2[2*n+1];
    for(int i = 0; i < n; i++){
        a[i] = A[i];
        b[i] = B[i];
        sum1 = sum1 + a[i] - b[i];
       
        dp[i] = 0;
        dp1[i] = -1e18;
    }
    pref1[0] = a[0];
    pref2[0] = b[0];
    for(int i = 1; i <= 2*n; i++){
        pref1[i] = pref1[i-1] + a[i % n];
        pref2[i] = pref2[i-1] + b[i % n];
    }
    long long int ans = 0;
    
    ans = max (ans, sum1);
    // ako ne uzimamo prvi element
    for(int i = 0; i < n; i++){
        if (i == 0){
            long long int sum = calculate(i, i + k-1, pref2);
            dp1[i] = a[i] - sum;
            
           // dp[i] = max(dp[i], dp1[i]);
           dp[i] = 0;
           dp1[i] = -1e18;
        }else{
            dp[i] = dp[i-1];
            long long int sum = calculate(i, i + k - 1, pref2);
            
            sum = a[i] - sum;
            if (i >= k){
                dp1[i] = sum + dp[i-k];
            }else{
                dp1[i] = sum;
            }
         
            dp1[i] = max(dp1[i], dp1[i-1] + a[i] - b[(i + k - 1) % n] );
            dp[i] = max(dp[i], dp1[i]);
        }
    }
    
    ans = max(ans, dp[n-1]);
    
    // ako uzimamo prvi element
    int vis[n];
    for (int i = 0; i < n; i++){
        dp[i] = -1e18;
        dp1[i] = -1e18;
        vis[i] = 0;
    }
    for (int i = 0; i < n; i++){
        if (i == 0){
            long long int sum = 0;
             sum = calculate(i, i + k-1, pref2);
            dp1[i] = a[i] - sum;
            dp[i] = dp1[i];
        }else{
            if (i >= k){
                dp[i] = dp[i-1];
                long long int sum = 0;
                sum = calculate(i, i + k-1, pref2);
                sum = a[i] - sum;
               
                dp1[i] = sum + dp[i-k];
                long long int ro = a[i];
                ro = ro - b[(i + k - 1) % n];
                dp1[i] = max(dp1[i], dp1[i-1] + ro);
            
                dp[i] = max(dp[i], dp1[i]);
                sum = 0;
                sum = calculate (i, n - 1, pref1) - calculate(i, n - 1, pref2);
                ans = max(ans, sum + dp[i-k]);
            }else{
                dp[i] = dp[i-1];
                long long int ro = a[i]; 
                if(vis[(i + k - 1) % n] == 0){
                    ro = ro - b[(i + k - 1) % n];
                }
                dp1[i] =  dp1[i-1] + ro;
                dp[i] = max(dp[i], dp1[i]);
            }
        }
    }
    ans = max(ans, dp[n-1]);
   return ans;
    
}

• Subtask 1: 13 / 13
• Subtask 2: 18 / 18
• Subtask 3: 31 / 31
• Subtask 4: 38 / 38