Strange Plants

problem

A mysterious $X$ [cm] plant grows in one place. This plant has the following mysterious properties.

• Say "nobiro" to this plant and it will grow $A$ [cm].
• Say "tidime" to this plant and it will grow $B$ [cm].
• If you say "karero" to this plant, it will be $0$ [cm].

However, this plant does not have a negative length. Specifically, when it grows from the state of $C$ [cm] to $D$ [cm] $(C + D \ lt 0)$, it is a plant. Stops growing when it reaches $0$ [cm].

Say one of "nobiro", "tidime", "karero" to this plant only once a day for $N$ days. Find the length [cm] of the plant after $N$ days.

output

Print the length of the plant after $N$ days. Also print a newline at the end.

Example

Input

10 30 10 3 nobiro nobiro tidime

Output

80

inputFormat

outputFormat

output

Print the length of the plant after $N$ days. Also print a newline at the end.

Example

Input

10 30 10 3 nobiro nobiro tidime

Output

80

样例

10 30 10
3
nobiro
nobiro
tidime

80