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hackercup / 2013 /finals /teleports.md
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2013 Problems
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Your house has **2 ≤ N ≤ 500,000** distinct rooms. None of the rooms have
doors, but every room has a one way teleport which takes you to a different
room. The same teleport will always go to the same room. You want to make sure
that every room can be reached from every room, via a series of teleports. To
do this, you are allowed to change the destination of some (or all) of the
teleports.
What is the sum of the minimum number of teleports you have to change to
achieve this, over all possible different starting configurations? Two
starting configurations are different if for some room, the outgoing teleport
goes to different rooms in the two configurations.
## Input
The first line contains a single integer **T**, **T** ≤ 20. **T** test cases
follow, where each test case consists of one integer: **N**
## Output
Output one single line with the sum of the minimum number of teleports you
have to change over all possible different starting configurations. Since this
number might be very big, output it modulo **1,000,000,007**