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51 lines
1.0 KiB
51 lines
1.0 KiB
3 years ago
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# Collatz Conjecture
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Welcome to Collatz Conjecture on Exercism's Erlang Track.
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If you need help running the tests or submitting your code, check out `HELP.md`.
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## Instructions
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The Collatz Conjecture or 3x+1 problem can be summarized as follows:
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Take any positive integer n. If n is even, divide n by 2 to get n / 2. If n is
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odd, multiply n by 3 and add 1 to get 3n + 1. Repeat the process indefinitely.
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The conjecture states that no matter which number you start with, you will
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always reach 1 eventually.
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Given a number n, return the number of steps required to reach 1.
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## Examples
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Starting with n = 12, the steps would be as follows:
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0. 12
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1. 6
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2. 3
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3. 10
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4. 5
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5. 16
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6. 8
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7. 4
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8. 2
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9. 1
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Resulting in 9 steps. So for input n = 12, the return value would be 9.
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## Source
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### Created by
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- @NobbZ
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### Contributed to by
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- @ErikSchierboom
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- @iHiD
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- @JordanAdams
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- @juhlig
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- @kytrinyx
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- @wojtii
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### Based on
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An unsolved problem in mathematics named after mathematician Lothar Collatz - https://en.wikipedia.org/wiki/3x_%2B_1_problem
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