Submission #1267781

#	Time	Username	Problem	Language	Result	Execution time	Memory
1267781		gustavo_d	Let's Win the Election (JOI22_ho_t3)	C++20	72 / 100	1260 ms	1010164 KiB

Main

#include <bits/stdc++.h>
using namespace std;

typedef long long ll;
typedef long double lfloat;

const int MAXN = 500;
const lfloat INF = 500000;

int a[MAXN], b[MAXN];
pair<int, int> input[MAXN];
lfloat dp[MAXN+1][MAXN+1][MAXN+1];

bool cmp(pair<int, int> i, pair<int, int> j) {
    if (i.second == j.second) return i.first < j.first;
    if (min(i.second, j.second) == -1) {
        return (i.second == -1) < (j.second == -1);
    }
    return i.second < j.second;
}

int main() {
    ios_base::sync_with_stdio(false); cin.tie(NULL);

    int n, K; cin >> n >> K;
    bool sub0 = true;
    for (int i=0; i<n; i++) cin >> input[i].first >> input[i].second;
    sort(input, input+n, cmp);
    int invalid = 0;
    for (int i=0; i<n; i++) {
        a[i] = input[i].first; b[i] = input[i].second;
        invalid += (b[i] == -1);
        // cout << a[i] << ' ' << b[i] << endl;
        if (b[i] != -1 and b[i] != a[i]) sub0 = false;
    }

    lfloat ans = INF;
    if (sub0) {
        ans = 0; lfloat cnt = 1;
        for (int i=1; i<=K; i++) {
            // cout << a[i-1] << ' ' << b[i-1] << endl;
            ans += a[i-1] / cnt;
            if (b[i-1] != -1) cnt++;
        }
    } else {
        for (int c=(sub0 ? (K - invalid) : 0); c<=min(K, n - invalid); c++) {
            for (int k=0; k<=K; k++) {
                for (int j=0; j<=K-c; j++) dp[0][k][j] = INF;
            }
            dp[0][0][0] = 0;
            for (int i=1; i<=n; i++) {
                // if (c == 1) cout << "i=" << i << endl;
                for (int k=0; k<=c; k++) {
                    if (K == n) {
                        int j = i - k;
                        dp[i][k][j] = min(
                            ((k == 0 or b[i-1] == -1) ? INF : (dp[i-1][k-1][j] + (lfloat)b[i-1] / (lfloat)k)),
                            (j == 0 ? INF : (dp[i-1][k][j-1] + (lfloat)a[i-1] / (1 + (lfloat)c)))
                        );
                        continue;
                    }
                    for (int j=0; j<=K-c; j++) {
                        dp[i][k][j] = min({
                            dp[i-1][k][j],
                            ((k == 0 or b[i-1] == -1) ? INF : (dp[i-1][k-1][j] + (lfloat)b[i-1] / (lfloat)k)),
                            (j == 0 ? INF : (dp[i-1][k][j-1] + (lfloat)a[i-1] / (1 + (lfloat)c)))
                        });
                        // if (c == 1) printf("%.5Lf ", dp[i][k][j]);
                    }
                    // if (c == 1) printf("\n");
                }
                // if (c == 1) printf("\n\n");
            }
            ans = min(ans, dp[n][c][K-c]);
        }
    }
    printf("%.5Lf", ans);

    return 0;
}

• Subtask 1: 5 / 5
• Subtask 2: 0 / 5
• Subtask 3: 11 / 11
• Subtask 4: 12 / 12
• Subtask 5: 33 / 33
• Subtask 6: 11 / 11
• Subtask 7: 0 / 23