POJ-1247

#include<iostream>
using namespace std;

bool isOod(int num){
	if(num%2==0){
		return false;
	}else{
		return true;
	}
}

int calCycleLength(int n){
	int len=0;
	if(n==1){
		return 1;
	}else{
		if(isOod(n)){
			n=3*n+1;
			len++;
			return len+calCycleLength(n);
		}else{
			n/=2;
			len++;
			return len+calCycleLength(n);
		}
	}
}

int main(int argc, char *argv[]){
	int input1, input2;
	int inputSmall, inputBig;
	int maxCycleLen;

	while(cin>>input1>>input2){
		maxCycleLen=0;
		if(input1>input2){
			inputSmall=input2;
			inputBig=input1;
		}else{
			inputSmall=input1;
			inputBig=input2;
		}
		for(int i=inputSmall;i<=inputBig;i++){
			int len=calCycleLength(i);
			if(len>maxCycleLen){
				maxCycleLen=len;
			}
		}

		cout<<input1<<" "<<input2<<" "<<maxCycleLen<<endl;
	}
	return 0;
}

POJ-1247

原文：http://blog.csdn.net/eddy_liu/article/details/46955967