Rohit and Debarshi likes to jump a lot. One day, they were getting bored and decided to play a new game. Both of them will make jumps of size x and y respectively. There is a path of length n and you are to find the number of positions which are visited by both Rohit and Debarshi . But, there are few manholes on the path and if one of them jumps on the position of the manhole,he falls into it and cannot continue further. Both of them are standing at position 0 initially.

NOTE :
Do not consider the position of the manhole in the final answer.

Constrains :
1<=x,y<=n<=1000

Input format:
n-length of path
s-path given in a string format, '_' means normal path, '.' means manhole
x,y - size of jump by Rohit,Debarshi respectively

Output format:
Print a single integer denoting the answer.