結果

問題 No.2157 崖
コンテスト
ユーザー norioc
提出日時 2025-05-30 01:01:35
言語 PyPy3
(7.3.15)
結果
TLE  
実行時間 -
コード長 8,043 bytes
コンパイル時間 395 ms
コンパイル使用メモリ 82,652 KB
実行使用メモリ 154,932 KB
最終ジャッジ日時 2025-05-30 01:01:49
合計ジャッジ時間 10,875 ms
ジャッジサーバーID
（参考情報） 		judge3 / judge5
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 * 3
other AC * 10 TLE * 1 -- * 11
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 # 

# https://github.com/tatyam-prime/SortedSet/blob/main/SortedSet.py
import math
from bisect import bisect_left, bisect_right
from typing import Generic, Iterable, Iterator, TypeVar

T = TypeVar('T')


class SortedSet(Generic[T]):
    BUCKET_RATIO = 16
    SPLIT_RATIO = 24

    def __init__(self, a: Iterable[T] = []) -> None:
        "Make a new SortedSet from iterable. / O(N) if sorted and unique / O(N log N)"
        a = list(a)
        n = len(a)
        if any(a[i] > a[i + 1] for i in range(n - 1)):
            a.sort()
        if any(a[i] >= a[i + 1] for i in range(n - 1)):
            a, b = [], a
            for x in b:
                if not a or a[-1] != x:
                    a.append(x)
        n = self.size = len(a)
        num_bucket = int(math.ceil(math.sqrt(n / self.BUCKET_RATIO)))
        self.a = [a[n * i // num_bucket: n * (i + 1) // num_bucket] for i in range(num_bucket)]

    def __iter__(self) -> Iterator[T]:
        for i in self.a:
            for j in i: yield j

    def __reversed__(self) -> Iterator[T]:
        for i in reversed(self.a):
            for j in reversed(i): yield j

    def __eq__(self, other) -> bool:
        return list(self) == list(other)

    def __len__(self) -> int:
        return self.size

    def __repr__(self) -> str:
        return "SortedSet" + str(self.a)

    def __str__(self) -> str:
        s = str(list(self))
        return "{" + s[1: len(s) - 1] + "}"

    def _position(self, x: T) -> tuple[list[T], int, int]:
        "return the bucket, index of the bucket and position in which x should be. self must not be empty."
        for i, a in enumerate(self.a):
            if x <= a[-1]: break
        return (a, i, bisect_left(a, x))

    def __contains__(self, x: T) -> bool:
        if self.size == 0: return False
        a, _, i = self._position(x)
        return i != len(a) and a[i] == x

    def add(self, x: T) -> bool:
        "Add an element and return True if added. / O(√N)"
        if self.size == 0:
            self.a = [[x]]
            self.size = 1
            return True
        a, b, i = self._position(x)
        if i != len(a) and a[i] == x: return False
        a.insert(i, x)
        self.size += 1
        if len(a) > len(self.a) * self.SPLIT_RATIO:
            mid = len(a) >> 1
            self.a[b:b + 1] = [a[:mid], a[mid:]]
        return True

    def _pop(self, a: list[T], b: int, i: int) -> T:
        ans = a.pop(i)
        self.size -= 1
        if not a: del self.a[b]
        return ans

    def discard(self, x: T) -> bool:
        "Remove an element and return True if removed. / O(√N)"
        if self.size == 0: return False
        a, b, i = self._position(x)
        if i == len(a) or a[i] != x: return False
        self._pop(a, b, i)
        return True

    def lt(self, x: T) -> T | None:
        "Find the largest element < x, or None if it doesn't exist."
        for a in reversed(self.a):
            if a[0] < x:
                return a[bisect_left(a, x) - 1]

    def le(self, x: T) -> T | None:
        "Find the largest element <= x, or None if it doesn't exist."
        for a in reversed(self.a):
            if a[0] <= x:
                return a[bisect_right(a, x) - 1]

    def gt(self, x: T) -> T | None:
        "Find the smallest element > x, or None if it doesn't exist."
        for a in self.a:
            if a[-1] > x:
                return a[bisect_right(a, x)]

    def ge(self, x: T) -> T | None:
        "Find the smallest element >= x, or None if it doesn't exist."
        for a in self.a:
            if a[-1] >= x:
                return a[bisect_left(a, x)]

    def __getitem__(self, i: int) -> T:
        "Return the i-th element."
        if i < 0:
            for a in reversed(self.a):
                i += len(a)
                if i >= 0: return a[i]
        else:
            for a in self.a:
                if i < len(a): return a[i]
                i -= len(a)
        raise IndexError

    def pop(self, i: int = -1) -> T:
        "Pop and return the i-th element."
        if i < 0:
            for b, a in enumerate(reversed(self.a)):
                i += len(a)
                if i >= 0: return self._pop(a, ~b, i)
        else:
            for b, a in enumerate(self.a):
                if i < len(a): return self._pop(a, b, i)
                i -= len(a)
        raise IndexError

    def index(self, x: T) -> int:
        "Count the number of elements < x."
        ans = 0
        for a in self.a:
            if a[-1] >= x:
                return ans + bisect_left(a, x)
            ans += len(a)
        return ans

    def index_right(self, x: T) -> int:
        "Count the number of elements <= x."
        ans = 0
        for a in self.a:
            if a[-1] > x:
                return ans + bisect_right(a, x)
            ans += len(a)
        return ans


from bisect import bisect_left, bisect_right
from itertools import accumulate


class IntervalSet:
    INF = 1 << 60

    def __init__(self):
        self.ss = SortedSet()
        self.ss.add((IntervalSet.INF * 2, IntervalSet.INF))  # (r, l)

    def __len__(self):
        return len(self.ss) - 1

    def __iter__(self):
        for r, l in self.ss:
            if l == IntervalSet.INF: break
            yield l, r

    def _overlap(self, l1: int, r1: int, l2: int, r2: int) -> int:
        """二つの半開区間 [l1, r1), [l2, r2) の重なりを求める"""
        assert l1 < r1 and l2 < r2
        start = max(l1, l2)
        end = min(r1, r2)
        return max(0, end - start)

    def overlap_length(self, l: int, r: int) -> int:
        """半開区間 [l, r) との重なり幅を返す"""
        assert 0 <= l < r < IntervalSet.INF
        t = self.ss.ge((l+1, -1))
        assert t is not None

        sr, sl = t  # [sl, sr)
        if r < sl:
            return 0

        if sl <= l and r <= sr:
            return r - l

        if r <= sr:
            return r - max(l, sl)

        wid = self._overlap(l, r, sl, sr)
        return wid + self.overlap_length(sr, r)

    def merge(self, l: int, r: int) -> tuple[int, int, int]:
        """
        半開区間 [l, r) をマージする。
        マージ後の半開区間と、入力 [l, r) との重なり幅を返す
        return: 既存の区間との重なり総幅, マージ後の半開区間(l, r)
        """
        assert 0 <= l < r
        t = self.ss.ge((l, -1))
        assert t is not None

        sr, sl = t  # [sl, sr)
        if r < sl:
            self.ss.add((r, l))
            return 0, l, r

        if sl <= l and r <= sr:
            return r-l, sl, sr

        self.ss.discard(t)
        start = min(l, sl)
        if r <= sr:
            self.ss.add((sr, start))
            return r-sl, start, sr

        wid, tl, tr = self.merge(start, r)
        wid += self._overlap(l, r, sl, sr)
        return wid, tl, tr


def find_interval(a: list, lo: int, hi: int) -> tuple[int, int, int]:
    """
    ソート済みリスト a の要素の lo 以上 hi 以下の個数と区間を返す
    return: 範囲内の個数, l, r
    """
    assert lo <= hi
    empty = 0, -1, -1  # 区間なし
    if not a or lo > a[-1] or hi < a[0]: return empty

    l = bisect_left(a, lo)
    r = bisect_right(a, hi) - 1
    if l > r: return empty
    return r-l+1, l, r


INF = 1 << 60
N, M = map(int, input().split())
D = []
for _ in range(N):
    D.append(sorted(map(int, input().split())))


# 距離 d 以下にできるか
def can(m):
    xs = D[0]
    for i in range(1, N):
        ins = IntervalSet()
        for x in xs:
            #print(f'merge {k=} {k+m+1=}')
            ins.merge(x, x+m+1)

        ys = set()
        for y in D[i]:
            if ins.overlap_length(y, y+1) == 1:
                ys.add(y)

        xs = ys
    #print(f'{xs=}')
    return len(xs) > 0


#can(2)
#exit()

lo = 0
hi = 10**9
ans = hi
while lo <= hi:
    m = (lo + hi) // 2
    if can(m):
        ans = min(ans, m)
        hi = m - 1
    else:
        lo = m + 1

if ans == 10**9:
    print(-1)
else:
    print(ans)
0