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
#include <iostream>
#include <string>

using namespace std;
int main(){
	int i,n,a,b,x;
	cin >> x >> a >> b >> n;
	int now = x;
	for(i=0;i<n;i++){
		string s; cin >> s;
		if(s[0]=='n'){
			now += a;
			if(now<0) now = 0;
		}
		if(s[0]=='t'){
			now += b;
			if(now<0) now = 0;
		}
		if(s[0]=='k'){
			now = 0;
		}
	}
	cout << now << endl;
}
