Submission #1061120

#	Time	Username	Problem	Language	Result	Execution time	Memory
1061120		thinknoexit	Copy and Paste 3 (JOI22_copypaste3)	C++17	6 / 100	7 ms	2396 KiB

copypaste3

#include<bits/stdc++.h>
using namespace std;
using ll = long long;
const ll Base = 31;
char s[2505];
ll dp[2505][2505], h[2505], pw[2505], H[2505];
ll A, B, C;
ll val(int l, int r) {
    return h[r] - h[l - 1] * pw[r - l + 1];
}
int main() {
    cin.tie(nullptr)->sync_with_stdio(false);
    int n;
    cin >> n;
    bool ch = 1;
    for (int i = 1;i <= n;i++) {
        cin >> s[i];
        ch &= s[i] == 'a';
        h[i] = h[i - 1] * B + (s[i] - 'a');
        pw[i] = pw[i - 1] * B;
    }
    cin >> A >> B >> C;
    if (ch) {
        vector<ll> dp(n + 2, 0);
        for (int i = 1;i <= n;i++) {
            dp[i] = dp[i - 1] + A;
            for (int j = 1;j < i;j++) {
                dp[i] = min(dp[i], (dp[j] + B) + A * (i % j) + C * (i / j));
            }
        }
        cout << dp[n] << '\n';
        return 0;
    }
    for (int i = 1;i <= n;i++) {
        for (int j = i + 1;j <= n;j++) {
            dp[i][j] = (j - i + 1) * A;
        }
    }
    for (int i = 1;i <= n;i++) {
        dp[i][i] = A;
        int cnt = 1;
        for (int j = i + 1;j <= n;j++) {
            if (s[i] == s[j]) {
                cnt++;
                dp[i][j] = min(dp[i][j], A * (j - i + 1 - cnt) + A + B + cnt * C);
            }
        }
    }
    for (int k = 1;k < n;k++) {
        for (int i = k + 1;i <= n;i++) {
            H[i] = val(i - k, i);
        }
        for (int i = 1;i <= n - k;i++) {
            int j = i + k;
            dp[i][j] = min(dp[i][j], A + dp[i + 1][j]);
            dp[i][j] = min(dp[i][j], dp[i][j - 1] + A);
            int cnt = 1, prev = j;
            for (int l = j + k + 1;l <= n;l++) {
                if (H[j] == H[l]) {
                    if (l - prev > k) {
                        cnt++;
                        prev = l;
                    }
                    dp[i][l] = min(dp[i][l], A * (l - i + 1 - cnt * k) + (dp[i][j] + B) + cnt * C);
                }
            }
        }
    }
    cout << dp[1][n] << '\n';
    return 0;
}

• Subtask 1: 1 / 1
• Subtask 2: 5 / 5
• Subtask 3: 0 / 14
• Subtask 4: 0 / 10
• Subtask 5: 0 / 32
• Subtask 6: 0 / 38