About 3n + 1 problem

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I submit my answer in Programming Challenges Judge(here http://www.programming-challenges.com[^]).I think my code of my is correct,but it show the result that is Answer Wrong.
Here is the code:

C++

// 3n+1.cpp : 定义控制台应用程序的入口点。
//

#include "stdafx.h"
#include <iostream>
using std::cin;
using std::cout;
using std::endl;

//declare function for calculate number of sequence of numbers
unsigned int NumOfSquence(unsigned int n);

int _tmain(int argc, _TCHAR* argv[])
{
	unsigned int i = 1,j = 1,temp = 0; 
	cin>>i>>j;
	//switch i and j,if(i > j)
	if(i > j){
	        temp = i;
	        i = j;
		j = temp;
	}
	unsigned int max = NumOfSquence(i);
	for(unsigned int k = i + 1;k <= j; k++){
		temp = NumOfSquence(k);
		if(temp > max){
			max = temp;
		}
	}
	cout<<i<<" "<<j<<" "<<max<<endl;
	return 0;
}

//the function of calculate number of sequence of numbers,whilch begins with n
// 16 8 4 2 1
unsigned int NumOfSquence(unsigned int n){
	unsigned int num = 1;
	while(n != 1){
		if(n % 2 == 0){
			n /=2;
		}
		else if(n % 2 == 1){
			n = 3 * n + 1;
		}
		num++;
	}
	return num;
}

Posted 14-Nov-12 2:06am

MLOVEternity

Updated 14-Nov-12 2:51am

v2

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Legor 14-Nov-12 9:28am

Is there any actual question related to this ?

MLOVEternity 15-Nov-12 10:23am

Here is the problem :
http://acm.uva.es/p/v1/100.html[^]

MLOVEternity 15-Nov-12 10:08am

@Jacques Loubser
This is an algorithmic problem in book,Programming challenges.It don't just calculate the answer of (3n + 1).

2 solutions

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Jacques Loubser · Answer 1 · 2012-11-14T03:51:00

Solution 1

Hi
Why must it be so complicated?

3n + 1 = (3 * n)+1

C++

unsigned int n = 0;
unsigned int output = 0;
output=( 3 * n ) + 1 ;

Posted 14-Nov-12 3:51am

Jacques Loubser

parths · Answer 2 · 2012-11-14T06:38:00

It seems from your code that you're trying find the longest sequence of steps for a Collatz conjecture[^] between 2 initial numbers.

In the function 'NumOfSquence' you should start from num = 0 instead of num = 1 to count the number of steps instead of the number values.

I hope this helps.