assignment2021scala/core1/collatz.scala
author Christian Urban <christian.urban@kcl.ac.uk>
Mon, 08 Nov 2021 23:17:51 +0000
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// Core Part 1 about the 3n+1 conjecture
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//============================================
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object C1 {
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//(1) Complete the collatz function below. It should
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//    recursively calculate the number of steps needed 
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//    until the collatz series reaches the number 1.
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//    If needed, you can use an auxiliary function that
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//    performs the recursion. The function should expect
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//    arguments in the range of 1 to 1 Million.
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def collatz(n: Long) : Long = ???
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//(2) Complete the collatz_max function below. It should
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//    calculate how many steps are needed for each number 
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//    from 1 up to a bound and then calculate the maximum number of
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//    steps and the corresponding number that needs that many 
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//    steps. Again, you should expect bounds in the range of 1
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//    up to 1 Million. The first component of the pair is
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//    the maximum number of steps and the second is the 
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//    corresponding number.
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def collatz_max(bnd: Long) : (Long, Long) = ???
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//(3) Implement a function that calculates the last_odd
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//    number in a collatz series.  For this implement an
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//    is_pow_of_two function which tests whether a number 
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//    is a power of two. The function is_hard calculates 
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//    whether 3n + 1 is a power of two. Again you can
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//    assume the input ranges between 1 and 1 Million,
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//    and also assume that the input of last_odd will not 
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//    be a power of 2.
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def is_pow_of_two(n: Long) : Boolean = ???
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def is_hard(n: Long) : Boolean = ???
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def last_odd(n: Long) : Long = ???
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}
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