1.6.1 3n+1问题 The 3n+1 problem

PC/UVA 110101/100

水题。数据范围大。需要预处理。之前处理过的+处理到这个地方的

//author: CHC
//First Edit Time:	2014-01-10 18:30
//Last Edit Time:	2014-01-10 18:30
//Filename:1.cpp
#include <iostream>
#include <cstdio>
#include <string.h>
#include <queue>
#include <algorithm>
using namespace std;
long long cs[1000001]={ 0 };
int main()
{
    for(int j=1;j<1000001;j++)
    {
        int i=1;
        long long n=j;
        while(n!=1)
        {
            if(n%2)n=n*3+1;
            else n/=2;
            if(n<j)
            {
                cs[j]=cs[n]+i;
                break;
            }
            ++i;
        }
        if(!cs[j]) cs[j]=i;
    }
    int a,b,c,d;
    while(~scanf("%d%d",&c,&d))
    {
        a=c,b=d;
        if(a>b)a^=b^=a^=b;
        int maxn=cs[a],maxi=a;
        for(int i=a+1;i<=b;i++)
            if(cs[i]>maxn)
            {
                maxn=cs[i];
                maxi=i;
            }
        printf("%d %d %d\n",c,d,maxn);
    }
    return 0;
}


The 3n + 1 problem

 

Consider the following algorithm to generate a sequence of numbers. Start with an integer n. If n is even, divide by 2. If n is odd, multiply by 3 and add 1. Repeat this process with the new value of n, terminating when n = 1. For example, the following sequence of numbers will be generated for n = 22:

22 11 34 17 52 26 13 40 20 10 5 16 8 4 2 1
It is  conjectured (but not yet proven) that this algorithm will terminate at  n = 1 for every integer  n. Still, the conjecture holds for all integers up to at least  1, 000, 000.

For an input n, the cycle-length of n is the number of numbers generated up to and including the 1. In the example above, the cycle length of 22 is 16. Given any two numbers i and j, you are to determine the maximum cycle length over all numbers between i and jincluding both endpoints.

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 1,000,000 and greater than 0.

Output

For each pair of input integers  i  and  j , output  i j  in the same order in which they appeared in the input and then the maximum cycle length for integers between and including  i  and  j . These three numbers should be separated by one space, with all three numbers on one line and with one line of output for each line of input.

Sample Input

1 10
100 200
201 210
900 1000

Sample Output

1 10 20
100 200 125
201 210 89
900 1000 174


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