Submission #533730

#	Time	Username	Problem	Language	Result	Execution time	Memory
533730		zxcvbnm	K blocks (IZhO14_blocks)	C++14	0 / 100	1 ms	332 KiB

blocks

#include <bits/stdc++.h>
using namespace std;
using ll = long long;
#define int ll
constexpr int nax = 105;
constexpr int INF = 1e12 + 5;
int dp[nax][nax];
int mx[nax][nax];

signed main() {
    ios_base::sync_with_stdio(false);
    cin.tie(nullptr);
    int n, k;
    cin >> n >> k;
    assert(n < nax);

    vector<int> a(n);
    for(int& i : a) {
        cin >> i;
    }

    if (n == k) {
        cout << accumulate(a.begin(), a.end(), 0LL);
        exit(0);
    }

    for(int i = 0; i < n; i++) {
        for(int j = 0; j < n; j++) {
            mx[i][j] = INF;
            dp[i][j] = INF;
        }
    }

    for(int i = 0; i < n; i++) {
        priority_queue<int> curr;
        for(int j = i; j < n; j++) {
            curr.push(a[j]);
            mx[i][j] = curr.top();
        }
    }

    for(int i = 0; i < n; i++) {
        dp[i][0] = 0;
        dp[i][1] = mx[0][i];
    }

//    for(int i = 0; i < n; i++) {
//        for(int j = 0; j < n; j++) {
//            cout << i << " " << j << ": " << mx[i][j] << "\n";
//        } cout << "\n";
//    }

    for(int splits = 2; splits <= k; splits++) {
        for(int i = splits-1; i < n; i++) {
            int l = splits-1, r = i-1, ans = splits-1;
            while(l <= r) {
                int mid = (l + r) / 2;
                int f1 = dp[mid-1][splits-1] + mx[mid][i];
                int f2 = dp[mid][splits-1] + mx[mid+1][i];
                if (f1 > f2) {
                    l = mid + 1;
                    ans = mid;
                }
                else {
                    r = mid - 1;
                }
            }

            dp[i][splits] = dp[ans][splits-1] + mx[ans+1][i];

//            for(int j = 0; j < i; j++) {
//                if (dp[j][splits-1] == INF) continue;
//                dp[i][splits] = min(dp[i][splits], dp[j][splits-1] + mx[j+1][i]);
//                cout << i << " " << splits << ": " << dp[j][splits-1] << " " << mx[j+1][i] << " "
//                     << dp[j][splits-1] + mx[j+1][i] << "\n";
//
////                cout << i << " " << splits << " " << j << ": " << dp[j][splits-1] << " " << mx[j+1][i]
////                     << " " << dp[j][splits-1] + mx[j+1][i] << "\n";
//            }
//            cout << i << " " << splits << ": " << dp[i][splits] << "\n";
        }
    }

    cout << dp[n-1][k] << "\n";

    return 0;
}

/*
6 5
6 9 3 8 2 5
*/

• Subtask 1: 0 / 14
• Subtask 2: 0 / 18
• Subtask 3: 0 / 21
• Subtask 4: 0 / 47