Problems from Waterloo Programming Contest 2010-07-10

Name
Fastest
Shortest
Authors
Full Solves
Ratio
Difficulty
Languages
Ideas0.14983211257%6.9Harden
Shopping0.1581121018387%4.6Mediumen
Stack Machine0.001391312168%5.8Harden
Tunnelling the Earth0.0023115313991%2.4Easyen