###### Category

###### Similar Problems

## 0736. Boxes

###### Time limit : 1000 ms

Memory limit : 64 mb

There are
two boxes. There are **a** balls in the first box, and **b** balls in the second box (**0** < **a** + **b** <**2147483648**). It
is possible to move balls from one box to another. From one box into another
one should move as many balls as the other box already contains. You have to
determine, whether it is possible to move all balls into one box.

**Input **

Contains two integers **a** and **b**, delimited by
space.

**Output **

Print
the number of moves which are required to move all balls into one box, or **-1** if it is impossible.

Samples

№ |
Input |
Output |

1 |
2 6 |
2 |

2 |
8 12 |
-1 |

3 |
7 9 |
4 |

Text from: acm.sgu.ru