RosettaCodeData/Task/Knapsack-problem-Bounded/Wren/knapsack-problem-bounded.wren

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import "./fmt" for Fmt
class Item {
construct new(name, weight, value, count) {
_name = name
_weight = weight
_value = value
_count = count
}
name { _name }
weight { _weight }
value { _value }
count { _count }
}
var items = [
Item.new("map", 9, 150, 1),
Item.new("compass", 13, 35, 1),
Item.new("water", 153, 200, 2),
Item.new("sandwich", 50, 60, 2),
Item.new("glucose", 15, 60, 2),
Item.new("tin", 68, 45, 3),
Item.new("banana", 27, 60, 3),
Item.new("apple", 39, 40, 3),
Item.new("cheese", 23, 30, 1),
Item.new("beer", 52, 10, 3),
Item.new("suntan cream", 11, 70, 1),
Item.new("camera", 32, 30, 1),
Item.new("T-shirt", 24, 15, 2),
Item.new("trousers", 48, 10, 2),
Item.new("umbrella", 73, 40, 1),
Item.new("waterproof trousers", 42, 70, 1),
Item.new("waterproof overclothes", 43, 75, 1),
Item.new("note-case", 22, 80, 1),
Item.new("sunglasses", 7, 20, 1),
Item.new("towel", 18, 12, 2),
Item.new("socks", 4, 50, 1),
Item.new("book", 30, 10, 2)
]
var n = items.count
var maxWeight = 400
var knapsack = Fn.new { |w|
var m = List.filled(n + 1, null)
for (i in 0..n) m[i] = List.filled(w + 1, 0)
for (i in 1..n) {
for (j in 0..w) {
m[i][j] = m[i-1][j]
for (k in 1..items[i - 1].count) {
if (k * items[i - 1].weight > j) break
var v = m[i - 1][j - k * items[i - 1].weight] + k * items[i - 1].value
if (v > m[i][j]) m[i][j] = v
}
}
}
var s = List.filled(n, 0)
var j = w
for (i in n..1) {
var v = m[i][j]
var k = 0
while (v != m[i - 1][j] + k * items[i - 1].value) {
s[i - 1] = s[i - 1] + 1
j = j - items[i - 1].weight
k = k + 1
}
}
return s
}
var s = knapsack.call(maxWeight)
System.print("Item Chosen Weight Value Number")
System.print("--------------------- ------ ----- ------")
var itemCount = 0
var sumWeight = 0
var sumValue = 0
var sumNumber = 0
for (i in 0... n) {
if (s[i] != 0) {
itemCount = itemCount + 1
var name = items[i].name
var number = s[i]
var weight = items[i].weight * number
var value = items[i].value * number
sumNumber = sumNumber + number
sumWeight = sumWeight + weight
sumValue = sumValue + value
Fmt.print("$-22s $3d $4d $2d", name, weight, value, number)
}
}
System.print("--------------------- ------ ----- ------")
Fmt.print("Items chosen $d $3d $4d $2d", itemCount, sumWeight, sumValue, sumNumber)