Statement

A tree was planted in the main square of Byteland many many years ago. It has been neglected in recent years and has grown incredibly large, causing an obstruction to traffic. In order to solve the situation, the Gardening Department of the city wants to cut some branches off the tree. The tree has N branches numbered from 0 to N-1. The Gardening Department sends N lumberjacks to cut down the branches as quickly as possible. The lumberjacks devise the following method. Everyone climbs up a branch (each on a different branch) and start working at the same time: the lumberjack sitting on branch i starts cutting down branch (i+1) \mod N. Unfortunately, if the i-th branch is cut, the lumberjack on the i-th branch will fall. If a lumberjack falls, he cannot continue cutting a branch. The Gardening Department wants to calculate the safety value of the cutting. The safety value is the number of lumberjacks who does not fall off the tree. The branches take different times to cut...