There are several test cases, ended by “0 0”.
For each test case, there are only one line containing two numbers separated by a blank, N and M, the original numbers of peaches and the numbers of peaches left(0<N,M<10^500).There is no leading zero.
输出格式
For each test case, you should output just a number K indicating the minimum time (in minutes) Lily needed to finish her illusion magic.
