题意：

      清楚明了。

注意：

       1.For any two numbers i and j you are to determine the maximum cycle length over all numbers between i and j

       并没有说i<j一定成立；

       2.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).

        i  和 j一定要输入的顺序与输出的顺序一样。

        于是就可以RE了！！！

#include
      
       int main(){    int n,m;    int sum;    int max;    int i;    int t,k;    while(scanf("%d %d",&n,&m)!=EOF)    {        max=1;        k=0;        if(n>m){k=1;t=m;m=n;n=t;}        for(int j=n;j<=m;j++)        {            i=j;            sum=1;            while(i!=1)        {            sum++;            if(i%2==0)i/=2;            else i=i*3+1;        }            if(sum>max)max=sum;        }        if(k==0)printf("%d %d %d\n",n,m,max);        else printf("%d %d %d\n",m,n,max);    }    return 0;}