a=['']*20
b=[0]*20
c=[0]*20
cnt=0
for i in range(20):
a[i],e,f=input().split()
b[i]=float(e)
if f=='P':
b[i]=0
continue
if f=='F':
c[i]=0
cnt+=1
continue
list(f)
c[i]=4-(ord(f[0])%65)
if f[1]=='+':
c[i]+=0.5
c[i]*=b[i]
print(sum(c)/sum(b))