Edward Elric has seen an electric bulletin board displaying the integer 1. He can perform the following operations A and B to change this value:
- Operation A: The displayed value is doubled.
- Operation B: The displayed value increases by K.
Edward Elric needs to perform these operations N times in total. Find the minimum possible value displayed in the board after N operations.
Input:
Single Line contains two space separated integers N and K.
Output:
Print the minimum possible value displayed in the board after N operations.
Constraints:
- 1≤N,K≤100000
- All input values are integers.
The value will be minimized when the operations are performed in the following order: A, A, A, A, B, B, B, B, B, B.
In this case, the value will change as follows: 1 → 2 → 4 → 8 → 16 → 26 → 36 → 46 → 56 → 66 → 76.
