oj.uz

Submission #802927

# Submission time Handle Problem Language Result Execution time Memory
802927 2023-08-02T15:53:29 Z myst6 Seesaw (JOI22_seesaw) C++14
0 / 100
 1 ms 320 KB 
#pragma GCC optimize("O2")

#include <bits/stdc++.h>

using namespace std;
using ll = long long;

int main() {
    cin.tie(0)->sync_with_stdio(0);
    int N;
    cin >> N;
    vector<ll> A(N);
    for (int i=0; i<N; i++) cin >> A[i];
    double bary[N][N];
    set<double> baries;
    memset(bary, 0, sizeof bary);
    for (int i=0; i<N; i++) {
        ll sum = 0;
        for (int j=i; j<N; j++) {
            sum += A[j];
            bary[i][j] = (double)sum / (double)(j - i + 1);
            baries.insert(bary[i][j]);
        }
    }
    double ans = 1e9;
    double tol = 1e-9;
    double dp[N][N];
    for (double upper_bound : baries) {
        if (upper_bound < bary[0][N-1]-tol) continue;
        memset(dp, 0, sizeof dp);
        for (int len=0; len<N; len++) {
            for (int i=0; i<N-len; i++) {
                if (len > 0) {
                    if (bary[i+1][i+len] < upper_bound+tol) {
                        dp[i][i+len] = min(bary[i][i+len], max(
                            dp[i+1][i+len],
                            dp[i][i+len-1]
                        ));
                    } else {
                        dp[i][i+len] = min(bary[i][i+len], dp[i][i+len-1]);
                    }
                } else {
                    dp[i][i+len] = bary[i][i+len];
                }
            }
        }
        // cout << upper_bound << ":\n";
        // for (int i=0; i<N; i++) {
        //     for (int j=0; j<N; j++) {
        //         cout << dp[i][j] << " ";
        //     }
        //     cout << "\n";
        // }
        // cout << "\n";
        ans = min(ans, upper_bound - dp[0][N-1]);
    }
    cout << setprecision(100) << ans << "\n";
    return 0;
}

Subtask #1
0 / 1.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 212 KB Output is correct
2 Incorrect 1 ms 320 KB Output isn't correct
3 Halted 0 ms 0 KB -

Subtask #2
0 / 33.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 212 KB Output is correct
2 Incorrect 1 ms 320 KB Output isn't correct
3 Halted 0 ms 0 KB -

Subtask #3
0 / 33.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 212 KB Output is correct
2 Incorrect 1 ms 320 KB Output isn't correct
3 Halted 0 ms 0 KB -

Subtask #4
0 / 33.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 212 KB Output is correct
2 Incorrect 1 ms 320 KB Output isn't correct
3 Halted 0 ms 0 KB -