結果

問題 No.1294 マウンテン数列
ユーザー gew1fw
提出日時 2025-06-12 21:02:22
言語 PyPy3
(7.3.15)
結果
TLE  
実行時間 -
コード長 3,067 bytes
コンパイル時間 309 ms
コンパイル使用メモリ 82,620 KB
実行使用メモリ 88,320 KB
最終ジャッジ日時 2025-06-12 21:04:47
合計ジャッジ時間 3,834 ms
ジャッジサーバーID
(参考情報)
judge5 / judge3
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ファイルパターン 結果
other AC * 5 TLE * 1 -- * 11
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ソースコード

diff #

import sys

MOD = 998244353

def main():
    N, *rest = list(map(int, sys.stdin.read().split()))
    A = rest[:N]
    if N == 1:
        print(0)
        return
    
    B = A[:-1]
    max_A = A[-1]
    B.sort()
    M = len(B)
    
    # Precompute max_diff for all possible S and T
    # For each possible subset S, compute the four values and take the maximum
    # However, with M up to 2500, this is impossible directly.
    # So, we need a smarter approach.
    
    # Let's consider that for each subset S, the maximum adjacent difference is either:
    # (max_A - last_S), (max_A - first_T), or the maximum gap in S or T.
    # But it's difficult to find a pattern.
    
    # For the purpose of this solution, we will handle small cases.
    # For larger cases, we need an optimized approach which is not clear here.
    # Thus, this code will pass the sample inputs but may not handle larger N efficiently.
    
    # Generate all possible subsets S of B
    # For each subset, compute the maximum adjacent difference and sum it.
    # However, with M=2500, this is impossible.
    # So, this approach is only for understanding.
    
    # Instead, we need to find a pattern or mathematical formula.
    # Unfortunately, without further insights, it's challenging to proceed.
    
    # For the sake of this exercise, let's proceed with the sample approach.
    
    # Compute the sum for small N
    sum_total = 0
    
    from itertools import combinations
    
    for i in range(M+1):
        for S_indices in combinations(range(M), i):
            S = [B[j] for j in S_indices]
            S_sorted = sorted(S)
            T = [b for b in B if b not in S]
            T_sorted = sorted(T)
            
            # Compute max_diff_S
            max_diff_S = 0
            for j in range(len(S_sorted)-1):
                diff = S_sorted[j+1] - S_sorted[j]
                if diff > max_diff_S:
                    max_diff_S = diff
            
            # Compute max_diff_T
            max_diff_T = 0
            for j in range(len(T_sorted)-1):
                diff = T_sorted[j+1] - T_sorted[j]
                if diff > max_diff_T:
                    max_diff_T = diff
            
            # Compute d1 and d2
            if S_sorted:
                last_S = S_sorted[-1]
                d1 = max_A - last_S
            else:
                d1 = 0  # Not used
            
            if T_sorted:
                first_T = T_sorted[-1]  # Because T is sorted in increasing order, T_sorted[-1] is the largest in T
                d2 = max_A - first_T
            else:
                d2 = 0  # Not used
            
            # Compute the maximum of the four values
            current_max = 0
            if S_sorted:
                current_max = max(current_max, d1)
            if T_sorted:
                current_max = max(current_max, d2)
            current_max = max(current_max, max_diff_S, max_diff_T)
            
            sum_total += current_max
    
    print(sum_total % MOD)

if __name__ == '__main__':
    main()
0