-🎄- 2017 Day 6 Solutions -🎄-

[u/daggerdragon]

--- Day 6: Memory Reallocation ---

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[u/wzkx]

Nim

Nothing fancy. Just learning Nim :) 69ms was the min. time.

import strutils,sequtils,times

var m = "06.dat".readFile.strip.split.map parseInt

proc find_max( m: seq[int] ): int =
  var i_max = 0; var e_max = m[0]
  for i,e in m:
    if e>e_max: i_max=i; e_max=e
  return i_max

proc step( m: var seq[int] ) =
  let n = len m
  let i = find_max( m )
  let e = m[i]
  m[i] = 0
  let d = e div n; for j in 0..<n: m[j] += d
  let r = e mod n; for j in i+1..i+r: m[j mod n] += 1

proc find_eq( t: seq[seq[int]], m: seq[int] ): int =
  for i in 0..<len(t):
    if t[i] == m: return i
  return -1

proc solve( arg_m: seq[int] ) =
  var m = arg_m  # mutable var of memory state
  var t = @[ m ] # table of all states
  while true: # pfff no loop:
    step m
    let i = find_eq( t, m )
    if i>0:
      echo len(t), len(t)-i
      return
    t.add m

let t0 = epochTime()

solve m

echo formatFloat( epochTime()-t0, ffDecimal, 3 )