Submission #532398

#	Time	Username	Problem	Language	Result	Execution time	Memory
532398		4fecta	The short shank; Redemption (BOI21_prison)	C++17	15 / 100	1825 ms	129884 KiB

prison

#include <bits/stdc++.h>
using namespace std;
#define ll long long
#define int ll
#define ld long double
#define pii pair<int, int>
#define f first
#define s second
#define boost() cin.tie(0), cin.sync_with_stdio(0)

const int MN = 4005;

int n, d, T, t[MN], dp[MN][MN];
bitset<MN> b[MN], ones[MN];

void solve(int j, int l, int r, int p1, int p2) {
    int mid = (l + r) >> 1, opt = 0;
    for (int i = p1; i <= min(p2, mid); i++) {
        int len = mid - i + 1;
        int tmp = (b[i] & (ones[len] << i)).count();
        if (dp[mid][j] > dp[i - 1][j - 1] + tmp) {
            dp[mid][j] = dp[i - 1][j - 1] + tmp;
            opt = i;
        }
    }
    if (l == r) return;
    solve(j, l, mid, p1, opt), solve(j, mid + 1, r, opt, p2);
}

int32_t main() {
    boost();

    cin >> n >> d >> T;
    for (int i = 1; i <= n; i++) cin >> t[i];
    for (int i = 1; i <= n; i++) ones[i] = ones[i - 1], ones[i][i - 1] = 1;
    for (int i = n; i > 0; i--) {
        b[i] = b[i + 1];
        if (t[i] > T) continue;
        int len = min(n, T - t[i] + 1);
        b[i] |= ones[len] << i;
    }
    memset(dp, 0x3f, sizeof(dp));
    dp[0][0] = 0;
    for (int i = 1; i <= d + 1; i++) solve(i, 1, n, 1, n);
    printf("%lld\n", dp[n][d + 1]);

    return 0;
}

• Subtask 1: 15 / 15
• Subtask 2: 0 / 10
• Subtask 3: 0 / 20
• Subtask 4: 0 / 10
• Subtask 5: 0 / 25
• Subtask 6: 0 / 20