結果

問題 No.1507 Road Blocked
ユーザー yuruhiya
提出日時 2021-05-15 18:20:50
言語 Crystal
(1.14.0)
結果
AC  
実行時間 90 ms / 2,000 ms
コード長 6,024 bytes
コンパイル時間 13,880 ms
コンパイル使用メモリ 295,220 KB
実行使用メモリ 22,740 KB
最終ジャッジ日時 2024-10-03 05:43:11
合計ジャッジ時間 17,894 ms
ジャッジサーバーID
(参考情報)
judge1 / 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 * 30
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 #
プレゼンテーションモードにする

# require "template"
lib C
fun strtoll(s : UInt8*, p : UInt8**, b : Int32) : Int64
end
class String
def to_i64
C.strtoll(self, nil, 10)
end
end
# require "graph/tree"
# require "./graph"
struct Edge(T)
include Comparable(Edge(T))
property to : Int32
property cost : T
def initialize(@to : Int32, @cost : T)
end
def <=>(other : Edge(T))
{cost, to} <=> {other.cost, other.to}
end
def to_s(io) : Nil
io << {to, cost}
end
def inspect(io) : Nil
io << "->#{to}(#{cost})"
end
end
struct Edge2(T)
include Comparable(Edge2(T))
property from : Int32
property to : Int32
property cost : T
def initialize(@from : Int32, @to : Int32, @cost : T)
end
def <=>(other : Edge2(T))
{cost, from, to} <=> {other.cost, other.from, other.to}
end
def reverse
Edge2(T).new(to, from, cost)
end
def to_s(io) : Nil
io << {from, to, cost}
end
def inspect(io) : Nil
io << "#{from}->#{to}(#{cost})"
end
end
class Graph(T)
getter graph : Array(Array(Edge(T)))
def initialize(size : Int32)
raise ArgumentError.new("Negative graph size: #{size}") unless size >= 0
@graph = Array.new(size) { Array(Edge(T)).new }
end
def initialize(size, edges : Array(Edge2(T)), *, undirected : Bool)
raise ArgumentError.new("Negative graph size: #{size}") unless size >= 0
@graph = Array.new(size) { Array(Edge(T)).new }
edges.each do |edge|
@graph[edge.from] << Edge.new(edge.to, edge.cost)
@graph[edge.to] << Edge.new(edge.from, edge.cost) if undirected
end
end
def add_edge(i : Int32, j : Int32, cost : T)
raise IndexError.new unless 0 <= i < size
raise IndexError.new unless 0 <= j < size
graph[i] << Edge(T).new(j, cost)
graph[j] << Edge(T).new(i, cost)
end
def add_edge_directed(i : Int32, j : Int32, cost : T)
raise IndexError.new unless 0 <= i < size
raise IndexError.new unless 0 <= j < size
graph[i] << Edge(T).new(j, cost)
end
delegate size, to: @graph
delegate :[], to: @graph
def each_edge : Nil
(0...size).each do |v|
graph[v].each do |edge|
yield Edge2(T).new(v, edge.to, edge.cost)
end
end
end
def each_edge(v : Int32) : Nil
graph[v].each do |edge|
yield Edge2(T).new(v, edge.to, edge.cost)
end
end
def edges : Array(Edge2(T))
result = [] of Edge2(T)
each_edge do |edge|
result << edge
end
result
end
def edges(v : Int32) : Array(Edge2(T))
result = [] of Edge2(T)
each_edge(v) do |edge|
result << edge
end
result
end
end
struct UnWeightedEdge
property from : Int32
property to : Int32
def initialize(@from, @to)
end
end
class UnWeightedGraph
getter size : Int32
getter graph : Array(Array(Int32))
def initialize(@size)
raise ArgumentError.new("Negative graph size: #{size}") unless size >= 0
@graph = Array.new(size) { Array(Int32).new }
end
def initialize(@size, edges : Array(UnWeightedEdge), *, undirected : Bool)
raise ArgumentError.new("Negative graph size: #{size}") unless size >= 0
@graph = Array.new(size) { Array(Int32).new }
edges.each do |edge|
@graph[edge.from] << edge.to
@graph[edge.to] << edge.from if undirected
end
end
delegate size, to: @graph
delegate :[], to: @graph
def add_edge(i : Int32, j : Int32)
raise IndexError.new unless 0 <= i < size
raise IndexError.new unless 0 <= j < size
graph[i] << j
graph[j] << i
end
def add_edge_directed(i : Int32, j : Int32)
raise IndexError.new unless 0 <= i < size
raise IndexError.new unless 0 <= j < size
graph[i] << j
end
end
class UnWeightedGraph
def subtree_size_dfs(v : Int32, p : Int32, result : Array(Int32)) : Int32
result[v] = 1 + self[v].select { |u| u != p }.sum { |u|
subtree_size_dfs(u, v, result)
}
end
def subtree_size(root : Int32)
result = Array.new(size, 0)
subtree_size_dfs(root, -1, result)
result
end
end
struct Mint
@@MOD = 998244353i64
def self.mod
@@MOD
end
def self.zero
Mint.new
end
@value : Int64
def initialize
@value = 0i64
end
def initialize(value)
@value = value.to_i64 % @@MOD
end
def initialize(m : Mint)
@value = m.value
end
protected def value=(value : Int64)
@value = value
end
getter value : Int64
def + : self
self
end
def - : self
Mint.new(value != 0 ? @@MOD - @value : 0)
end
def +(m)
self + m.to_mint
end
def +(m : Mint)
result = Mint.new
result.value = @value + m.value
result.value -= @@MOD if result.value >= @@MOD
result
end
def -(m)
self - m.to_mint
end
def -(m : Mint)
result = Mint.new
result.value = @value - m.value
result.value += @@MOD if result.value < 0
result
end
def *(m)
result = Mint.new
result.value = @value * Mint.new(m).value % @@MOD
result
end
def /(m)
raise DivisionByZeroError.new if m == 0
a, b, u, v = m.to_i64, @@MOD, 1i64, 0i64
while b != 0
t = a // b
a -= t * b
a, b = b, a
u -= t * v
u, v = v, u
end
Mint.new(@value * u)
end
def //(m)
self / m
end
def **(m : Int)
t, res = self, Mint.new(1)
while m > 0
res *= t if m.odd?
t *= t
m >>= 1
end
res
end
def ==(m)
@value == m.to_i64
end
def !=(m)
@value != m.to_i64
end
def succ
self + 1
end
def pred
self - 1
end
def to_i64 : Int64
@value
end
delegate to_s, to: @value
delegate inspect, to: @value
end
struct Int
def to_mint : Mint
Mint.new(self)
end
end
class String
def to_mint : Mint
Mint.new(self)
end
end
n = read_line.to_i
m = Mint.new(n.to_i64 * ~-n // 2)
g = UnWeightedGraph.new n, (1..n - 1).map {
a, b = read_line.split.map &.to_i.pred
UnWeightedEdge.new(a, b)
}, undirected: true
puts g.subtree_size(0)[1..].sum { |size|
size2 = Mint.new(size.to_i64 * (n - size))
(m - size2) / m
} / n.pred
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