Initial data commit

Task/Knapsack-problem-Unbounded/Ruby/knapsack-problem-unbounded.rb

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+KnapsackItem = Struct.new(:volume, :weight, :value)
+panacea = KnapsackItem.new(0.025, 0.3, 3000)
+ichor   = KnapsackItem.new(0.015, 0.2, 1800)
+gold    = KnapsackItem.new(0.002, 2.0, 2500)
+maximum = KnapsackItem.new(0.25,  25,  0)
+
+max_items = {}
+for item in [panacea, ichor, gold]
+  max_items[item] = [(maximum.volume/item.volume).to_i, (maximum.weight/item.weight).to_i].min
+end
+
+maxval = 0
+solutions = []
+
+0.upto(max_items[ichor]) do |i|
+  0.upto(max_items[panacea]) do |p|
+    0.upto(max_items[gold]) do |g|
+      break if i*ichor.weight + p*panacea.weight + g*gold.weight > maximum.weight
+      break if i*ichor.volume + p*panacea.volume + g*gold.volume > maximum.volume
+      val = i*ichor.value + p*panacea.value + g*gold.value
+      if val > maxval
+        maxval = val
+        solutions = [[i, p, g]]
+      elsif val == maxval
+        solutions << [i, p, g]
+      end
+    end
+  end
+end
+
+puts "The maximal solution has value #{maxval}"
+solutions.each do |i, p, g|
+  printf "  ichor=%2d, panacea=%2d, gold=%2d -- weight:%.1f, volume=%.3f\n",
+    i, p, g,
+    i*ichor.weight + p*panacea.weight + g*gold.weight,
+    i*ichor.volume + p*panacea.volume + g*gold.volume
+end