UVa Problem 100 The 3n+1 problem （3n+1 问题）

参考：https://blog.csdn.net/metaphysis/article/details/6431937

#include <iostream>
#include <cstdio>
#include <cstring>
using namespace std;
typedef long long ll;
ll a,b;
ll length(ll x)
{
    ll l=1;
    while (x!=1)
    {
        if (x%2==1)
        {
            x=3*x+1;
        }
        else
        {
            x=x/2;
        }
        l++;
    } 
    return l;
}
int main()
{
//    freopen("text.txt","r",stdin);
    while (scanf("%lld %lld",&a,&b)!=EOF)
    {
        ll ma=0;
        for (ll i=min(a,b);i<=max(a,b);i++)//注意输入要先排大小！ 
        {
            ma=max(ma,length(i));
        }
        printf("%lld %lld %lld
",a,b,ma);
    }
    
    return 0;
 }