結果

問題 No.2019 Digits Filling for All Substrings
コンテスト
ユーザー lam6er
提出日時 2025-03-31 18:01:29
言語 PyPy3
(7.3.15)
結果
TLE  
実行時間 -
コード長 2,333 bytes
コンパイル時間 290 ms
コンパイル使用メモリ 82,676 KB
実行使用メモリ 92,404 KB
最終ジャッジ日時 2025-03-31 18:02:15
合計ジャッジ時間 4,345 ms
ジャッジサーバーID
（参考情報） 		judge5 / judge1
このコードへのチャレンジ
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ファイルパターン 結果
sample AC * 4
other TLE * 1 -- * 29
権限があれば一括ダウンロードができます

ソースコード

diff # 

import sys
from collections import defaultdict

MOD = 998244353

def main():
    N = int(sys.stdin.readline())
    S = sys.stdin.readline().strip()
    
    answer = 0
    dp_prev = defaultdict(int)  # (mod, has_first) -> count
    
    for i in range(N):
        current_char = S[i]
        new_dp = defaultdict(int)
        
        # Case 1: new substring [i]
        if current_char == '?':
            new_dp[(0, False)] += 1
            new_dp[(0, True)] += 3
            new_dp[(1, True)] += 3
            new_dp[(2, True)] += 3
        else:
            d = int(current_char)
            if d == 0:
                new_dp[(0, False)] += 1
            else:
                mod = d % 3
                new_dp[(mod, True)] += 1
        
        # Case 2: extend previous substrings
        for (prev_mod, prev_has_first), cnt in dp_prev.items():
            if current_char == '?':
                if not prev_has_first:
                    # Transition for ? where previous state has_first is False
                    new_dp[(0, False)] += cnt
                    new_dp[(0, True)] += 3 * cnt
                    new_dp[(1, True)] += 3 * cnt
                    new_dp[(2, True)] += 3 * cnt
                else:
                    # Transition for ? where previous state has_first is True
                    for m in [0, 1, 2]:
                        d_count = 4 if m == 0 else 3
                        new_mod = (prev_mod + m) % 3
                        new_dp[(new_mod, True)] += cnt * d_count
            else:
                d = int(current_char)
                if not prev_has_first:
                    if d == 0:
                        new_dp[(0, False)] += cnt
                    else:
                        new_mod = d % 3
                        new_dp[(new_mod, True)] += cnt
                else:
                    new_mod = (prev_mod + d) % 3
                    new_dp[(new_mod, True)] += cnt
        
        # Calculate contribution for current R
        current_contribution = 0
        current_contribution += new_dp.get((0, False), 0)
        current_contribution += new_dp.get((0, True), 0)
        answer = (answer + current_contribution) % MOD
        
        # Update dp_prev for next iteration
        dp_prev = new_dp
    
    print(answer % MOD)

if __name__ == '__main__':
    main()
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