100 - The 3n + 1 problem

1437027969.cpp

#include <stdio.h>

int main()
{
	unsigned  long int x,z,i,j , n, max;
	while (scanf("%lu %lu", &x, &z) == 2)
	{
		if (x > z)
		{
			i = z;
			j = x;
		}
		else
		{
			i = x;
			j = z;
		}
		max = 0;
		for (unsigned long int k = i; k <= j; k++)
		{
			unsigned long int temp = k;
			n = 1;
			while (temp != 1)
			{
				n++;
				if (temp % 2 == 0)
					temp /= 2;
				else
					temp = 3 * temp + 1;
			}
			if (n > max)
				max = n;
		}
		printf("%lu %lu %lu\n", x, z, max);	
	}
}