The 3n + 1 problem X79188


Statement
 

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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

Given an input n, it is possible to determine the number of numbers printed before and including the 1 is printed. 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 and including both i and j.

Input

The input will consist of a series of pairs of integers i and j, one pair of integers per line. All integers will be less than 10,000 and greater than 0. You should process all pairs of integers and for each pair 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

For each pair of input integers i and j 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 and with one line of output for each line of input. 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).

Public test cases
  • Input

    1 10
    100 200
    201 210
    900 1000
    

    Output

    1 10 20
    100 200 125
    201 210 89
    900 1000 174
    
  • Information
    Author
    Prof. Carlos de Salles, DEINF/UFMA.
    Language
    English
    Official solutions
    C
    User solutions
    C