这个题目直接用的暴力枚举，但是还是WA了几次

原因是这句话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. 

注意i可能大于j，此时需要交换顺序，但是输出的时候还会是原始顺序

比如 输入1 10 输出 1 10 20 ；输入10 1 输出 10 1 20

因此交换i和j需要用标志位记录一下

Source Code

Problem: 1207		User: yangliuACMer
Memory: 244K		Time: 16MS
Language: C++		Result: Accepted

//暴力枚举
//21:22
#include <iostream>
using namespace std;

int main(){
	int i,j,k,count,max,newk,temp;
	bool flag;
	while(cin>>i>>j){
		max = 1;
		flag = true;
		if(i > j){
			temp = i;
			i = j;
			j = temp;
			flag = false;
		}
		for(k = i; k <= j; k++){
			count = 1;
			newk = k;//注意计算循环节的时候k的值会发生变化
			while(newk != 1){
				count++;
				if(newk % 2) newk = 3 * newk + 1;
				else newk/=2;
			}
			if(count > max) max = count;
		}
		if(flag)
			cout<<i<<" "<<j<<" "<<max<<endl;
		else cout<<j<<" "<<i<<" "<<max<<endl;
	}
	return 0;
}
//21:42