Time limit 2000/4000/4000/4000 ms. Memory limit 65000/65000/65000/65000 Kb. Problem taken from UVA site.
The 3n + 1 problem
Background:
Problems in Computer Science are often classified as belonging
to a certain class of problems (e.g., NP, Unsolvable, Recursive).
In this problem you will be analyzing a property of an algorithm
whose classification is not known for all possible inputs.
Question:
Consider the following algorithm:
1. input n
2. print n
3. if n = 1 then STOP
4. if n is odd then N ← 3N+1
5. else N ← N/2
6. GOTO 2
Given the input 22, the following sequence of numbers
will be printed 22 11 34 17 52 26 13 40 20 10 5 16 8 4 2 1
It is conjectured that the algorithm above will terminate
(when a 1 is printed) for any integral input value. Despite
the simplicity of the algorithm, it is unknown whether
this conjecture is true. It has been verified, however,
for all integers n such that 0 < n < 1,000,000 (and,
in fact, for many more numbers than this.)
Given an input n, it is possible to determine the number
of numbers printed (including the 1). For a given n this
is called the cycle-length of n. In the example above,
the cycle length of 22 is 16.
For any two numbers i and j you are to determine the
maximum cycle length over all numbers between i and j.
Input specification
The input will consist of a pair of integers i and j.
All integers will be less than 1,000,000 and greater than 0.
You must determine the maximum cycle length over all
integers between and including i and j.
You can assume that no operation overflows a 32-bit
integer.
Output specification
You should output i, j, and the maximum cycle length
for integers between and including i and j. These
three numbers should be separated by at least one
space with all three numbers on one line. The integers
i and j must appear in the output in the same order
in which they appeared in the input and should be
followed by the maximum cycle length (on the same
line).
Sample Input I
1 10
100 200
201 210
900 1000
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Sample Output I
1 10 20
100 200 125
201 210 89
900 1000 174
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Для отправки решений необходимо выполнить вход.
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