Let us consider the set of integer numbers between 1 and N inclusive. Let us order them lexicographically (i.e. like in the vocabulary), for example, for N = 11 the order would be: 1, 10, 11, 2, 3, 4, 5, 6, 7, 8, 9.
Let us denote the position of the number K in this ordering as Q(N, K). For example, Q(11, 2) = 4. Given numbers K and M find the smallest N such that Q(N, K) = M.
Input
Input file contains two integer numbers K and M (1 <= K, M <= 10^9) separated by a space.
Process to the end of file.
Output
If such N that Q(N, K) = M exists then write to the output file the smallest such N, otherwise write 0.
Sample Input
2 4
2 1
100000001 1000000000
1000000000 11
Sample Output
11
0
100000000888888879
0