We are working for a logistics company that handles cargo shipping in containers.
Each container has fixed dimensions: 2.5 meters in width, 2.5 meters in height, and 6 meters in length.
The company receives orders to ship various items, each with specific dimensions.
We want to determine how to load the items into the containers to minimize the number of containers used, while ensuring that no items are rotated and all items fit within the container's dimensions.

Example input data:
1. items.csv
item_id,width,height,length,quantity
I1,1.2,0.5,3.0,10
