Submission #1476386

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Source Code Expand

# import sequtils, strutils, strscans, algorithm, math, future, sets, queues, tables # for yukicoder (0.17.1)
import sequtils, strutils, algorithm, math, future, sets, queues, tables # for AtCoder (0.13.0)
template getLine: string = stdin.readLine
template getInteger: int = getLine.parseInt
template getBiggestInteger: int64 = getLine.parseBiggestInt
template getIntSeq: seq[int] = getLine.split.map(parseInt)
template getBigIntSeq: seq[int64] = getLine.split.map(parseBiggestInt)

var
  edge: seq[seq[int]]
  A: seq[int64]

proc dfs(v, par: int): int64 =
  if par != -1 and edge[v].len == 1:
    return A[v]

  var path = newSeq[int64]()
  for c in edge[v]:
    if c != par:
      path.add(dfs(c, v))
      if path[^1] == -1:
        return -1
  let p_path = 2.int64 * A[v] - path.sum
  if 0 <= p_path and path.max <= A[v] and A[v] <= path.sum:
    return p_path
  else:
    return -1

when isMainModule:
  let
    N = getInteger
  A = getBigIntSeq
  edge = newSeqWith(N, newSeq[int]())
  for _ in 0..<N-1:
    let
      tmp = getIntSeq.mapIt(it-1)
      (a, b) = (tmp[0], tmp[1])
    edge[a].add(b)
    edge[b].add(a)
  let P = dfs(0, -1)
  if edge[0].len == 1:
    echo(if P == A[0]: "YES" else: "NO")
  else:
    echo(if P == 0: "YES" else: "NO")

Submission Info

Compile Error

Hint: system [Processing]
Hint: Main [Processing]
Hint: sequtils [Processing]
Hint: strutils [Processing]
Hint: parseutils [Processing]
Hint: algorithm [Processing]
Hint: math [Processing]
Hint: times [Processing]
Hint: future [Processing]
Hint: macros [Processing]
Hint: sets [Processing]
Hint: os [Processing]
Hint: posix [Processing]
Hint: hashes [Processing]
Hint: etcpriv [Processing]
Hint: queues [Processing]
Hint: tables [Processing]
Main.nim(5, 10) Hint: 'getBiggestInteger' is declared but not used [XDeclaredButNotUsed]
Hint:  [Link]
Hint: operation successful (24525 lines compiled; 2.106 sec total; 23.240MB; Release Build) [SuccessX]

Judge Result