oj.uz

Submission #61842

# Submission time Handle Problem Language Result Execution time Memory
61842 2018-07-26T20:42:42 Z Benq Homecoming (BOI18_homecoming) C++11
100 / 100
 289 ms 119488 KB 
#include <bits/stdc++.h>
#include <ext/pb_ds/tree_policy.hpp>
#include <ext/pb_ds/assoc_container.hpp>

using namespace std;
using namespace __gnu_pbds;
 
typedef long long ll;
typedef long double ld;
typedef complex<ld> cd;

typedef pair<int, int> pi;
typedef pair<ll,ll> pl;
typedef pair<ld,ld> pd;

typedef vector<int> vi;
typedef vector<ld> vd;
typedef vector<ll> vl;
typedef vector<pi> vpi;
typedef vector<pl> vpl;
typedef vector<cd> vcd;

template <class T> using Tree = tree<T, null_type, less<T>, rb_tree_tag,tree_order_statistics_node_update>;

#define FOR(i, a, b) for (int i=a; i<(b); i++)
#define F0R(i, a) for (int i=0; i<(a); i++)
#define FORd(i,a,b) for (int i = (b)-1; i >= a; i--)
#define F0Rd(i,a) for (int i = (a)-1; i >= 0; i--)

#define sz(x) (int)(x).size()
#define mp make_pair
#define pb push_back
#define f first
#define s second
#define lb lower_bound
#define ub upper_bound
#define all(x) x.begin(), x.end()

const int MOD = 1000000007;
const ll INF = 1e18;
const int MX = 2000001;

#include "homecoming.h"

ll cb[2*MX], dp[MX][2][2];

ll get(int l, int r) { 
    // cout << "OH " << cb[r+1]-cb[l] << "\n";
    return cb[r+1]-cb[l]; 
}

long long int solve(int N, int K, int *A, int *B) {
    F0R(i,2*N) cb[i+1] = cb[i]+B[i%N];
    
    ll ans = 0;
    F0R(i,N) F0R(j,2) F0R(k,2) dp[i][j][k] = -INF;
    dp[0][0][0] = 0, dp[0][1][1] = A[0]-get(0,K-1);
    FOR(i,1,N) {
        F0R(j,2) {
            dp[i][0][j] = max(dp[i-1][0][j],dp[i-1][1][j]);
            if (j == 0 || i+K-1 < N) {
                dp[i][1][j] = max(dp[i-1][1][j]+A[i]-B[(i+K-1)%N],dp[i-1][0][j]+A[i]-get(i,i+K-1));
            } else {
                dp[i][1][j] = max(dp[i-1][1][j]+A[i],dp[i-1][0][j]+A[i]-get(i,N-1));
            }
            // cout << "OH " << i << " " << j << " " << dp[i][0][j] << " " << dp[i][1][j] << "\n";
        } 
    }
    F0R(j,2) F0R(k,2) ans = max(ans,dp[N-1][j][k]);
    return ans;
}

/*int main() {
    ios_base::sync_with_stdio(0); cin.tie(0);
    int A[3] = {40, 80, 100};
    int B[3] = {140, 0, 20};
    cout << solve(3,2,A,B);
}*/

/* Look for:
* the exact constraints (multiple sets are too slow for n=10^6 :( ) 
* special cases (n=1?)
* overflow (ll vs int?)
* array bounds
*/

Subtask #1
13.0 / 13.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 376 KB Output is correct
2 Correct 2 ms 484 KB Output is correct
3 Correct 2 ms 560 KB Output is correct
4 Correct 2 ms 640 KB Output is correct
5 Correct 3 ms 696 KB Output is correct

Subtask #2
18.0 / 18.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 376 KB Output is correct
2 Correct 2 ms 484 KB Output is correct
3 Correct 2 ms 560 KB Output is correct
4 Correct 2 ms 640 KB Output is correct
5 Correct 3 ms 696 KB Output is correct
6 Correct 3 ms 828 KB Output is correct
7 Correct 3 ms 828 KB Output is correct
8 Correct 2 ms 828 KB Output is correct
9 Correct 4 ms 828 KB Output is correct
10 Correct 4 ms 828 KB Output is correct

Subtask #3
31.0 / 31.0

# Verdict Execution time Memory Grader output
1 Correct 67 ms 28152 KB Output is correct
2 Correct 7 ms 28152 KB Output is correct
3 Correct 289 ms 110152 KB Output is correct
4 Correct 5 ms 110152 KB Output is correct
5 Correct 15 ms 110152 KB Output is correct

Subtask #4
38.0 / 38.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 376 KB Output is correct
2 Correct 2 ms 484 KB Output is correct
3 Correct 2 ms 560 KB Output is correct
4 Correct 2 ms 640 KB Output is correct
5 Correct 3 ms 696 KB Output is correct
6 Correct 3 ms 828 KB Output is correct
7 Correct 3 ms 828 KB Output is correct
8 Correct 2 ms 828 KB Output is correct
9 Correct 4 ms 828 KB Output is correct
10 Correct 4 ms 828 KB Output is correct
11 Correct 67 ms 28152 KB Output is correct
12 Correct 7 ms 28152 KB Output is correct
13 Correct 289 ms 110152 KB Output is correct
14 Correct 5 ms 110152 KB Output is correct
15 Correct 15 ms 110152 KB Output is correct
16 Correct 287 ms 110316 KB Output is correct
17 Correct 92 ms 110316 KB Output is correct
18 Correct 169 ms 110316 KB Output is correct
19 Correct 198 ms 110316 KB Output is correct
20 Correct 191 ms 119488 KB Output is correct
21 Correct 184 ms 119488 KB Output is correct