func _ready():
	var A = Item.new("A", 0.1)
	var B = Item.new("B", 0.5)
	var C = Item.new("C", 0.7)
	for i in 10:
		print(drop_random_item([A, B, C]).name)

class Item:
	var chance
	var name
	func _init(name, c):
		self.name = name
		self.chance = c

func drop_random_item(items):
	var total_chance_sum = 0
	for i in items.size():
		total_chance_sum += items[i].chance
	var r = rand_range(0, total_chance_sum)
	var current_sum = 0
	for i in items.size():
		if (current_sum <= r && r < current_sum + items[i].chance): return items[i]
		current_sum += items[i].chance