collatz.cpp

/* TODO: write a program to test the collatz conjecture.  This conjecture
 * considers the following process:
 * Start with any (positive) integer n and then transform it as follows:
 * -- if n == 1, stop
 * -- if n is even, divide it by 2 (n --> n/2)
 * -- if n is odd, multiply b 3 and add 1 (n --> 3n+1)
 * Conjecture: this process always stops after a finite number of steps,
 * no matter what value of n you start with.
 *
 * Your program should work as follows:
 * 1. read an integer
 * 2. see how many steps the above process takes before you hit 1
 * 3. print # of steps
 * 4. go back to (1) until stdin has no more integers to read.
 * */
#include <iostream>
using std::cin;
using std::cout;

int main()
{
	int n;
	while (cin>>n) {
		int steps =0;
		while (n!=1) {
			if (n%2==0) {
				n=n/2;
			}else {
				n=3*n+1;;
			}
			steps++;
		}
		cout<< steps <<std::endl;
	}

	return 0;
}

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