fml

-- Assuming the container is connected to the left side of the computer
local container = peripheral.wrap("bottom")

-- Assuming the item you want to count is "minecraft:diamond"
local itemToCount = "minecraft:diamondore"

-- Get the inventory size of the container
local size = container.size()

-- Loop through each slot and count the number of items
local itemCount = 0
for slot = 1, size do
  local stack = container.getStackInSlot(slot)
  if stack and stack.name == itemToCount then
    itemCount = itemCount + stack.size
  end
end

-- Print the total count of the item
print("Total count of " .. itemToCount .. " in container: " .. itemCount)