You have a large pile of ropes and some matches. All you know about the ropes:

• Each rope has a different length
• Each rope burns completely (starting from one end) in exactly 64 minutes
• Each rope has non-uniform density, meaning it is thicker at some points than others. Consequently, burning half a rope cannot be guaranteed to take 32 minutes.

The goal is to identify when exactly 63 minutes have passed.