NYOJ-271 The 3n + 1 problem

2012-06-0822:26:07题目链接：http://acm.nyist.net/JudgeOnline/problem.php?pid=271

/*

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/*
#include<stdio.h>
#include<string.h>
int visit[10000];

int fun(int a,int b,int i)
{
	int num=1;
	while(i!=1)
	{
		if(i&1)
		{
			i=3*i+1;
			if(i<=b&&i>=a)
				visit[i]=1;
		}
		else
		{
			i>>=1;
			if(i<=b&&i>=a)
				visit[i]=1;
		}
		++num;
	}
	return num;
}

int main()
{
	int a,b,i,flag,t,ans,temp;
	while(scanf("%d%d",&a,&b)!=EOF)
	{
		memset(visit,0,sizeof(10000));
		ans=1;
		flag=0;
		if(a>b)
		{
			flag=1;
			t=a;
			a=b;
			b=t;
		}
		for(i=a;i<=b;++i)
			if(!visit[i])
			{
				temp=fun(a,b,i);
				if(temp>ans)
					ans=temp;
			}
		if(flag)
			printf("%d %d %d\n",b,a,ans);
		else
			printf("%d %d %d\n",a,b,ans);
	}
	return 0;
}//超时
*/
 
#include <iostream>
using namespace std;
int d[10003];

int main()
{
  //  freopen("input.txt","r",stdin);
  //  freopen("output.txt","w",stdout);//会自动生成
    int i,j,t;
    for(int k=2;k<10003;k++)//打表
    {
        t=k;
        while(1!=t)
        {
            if(t&1)
            {
                t=t*3+1;
            }
            else  t>>=1;
            d[k]++;
        }
    }
    while(cin>>i>>j)
    {

        int max=0,t=0;
        cout<<i<<" "<<j<<" ";
        if(i>j)//交换i和j的值
        {
            i^=j;j^=i;i^=j;
        }
        for(int k=i;k<=j;k++)
        {


          if(max<d[k])
            max=d[k];
        }


        cout<<max+1<<endl;
    }
    return 0;
}

 

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