g,c,p=map(int,input().split())
s=input()
f=[0]*len(s)
cnt=0

for i in range(len(s)):
    if s[i] =='G' and p > 0:
            p -= 1
            cnt+=3
    elif s[i] =='C' and g > 0:
            g -= 1
            cnt+=3
    elif s[i] =='P' and c > 0:
            c -= 1
            cnt+=3
    else:
        f[i] += 1
        
for i in range(len(s)):
    if f[i] == 0:
        continue
        
    if s[i] =='G' and g > 0:
            g -= 1
            cnt+=1
    elif s[i] =='C' and c > 0:
            c -= 1
            cnt+=1
    elif s[i] =='P' and p > 0:
            p -= 1
            cnt+=1
            
print(cnt)