```
class Solution(object):
def getHint(self, secret, guess):
bulls = 0
cows = 0
cowcount = [0]*10
for i in range(10):
s = str(i)
cowcount[i] = min(secret.count(s),guess.count(s))
for i in range(len(secret)):
if secret[i] == guess[i]:
bulls += 1
j = int(secret[i])
cowcount[j] -= 1
for s in cowcount:
cows += int(s)
return str(bulls)+"A"+str(cows)+"B"
```

Check for cows (the number of cows for a digit can't ever exceed secret, hence the min). Then check for bulls -- every bull is one less cow. Then calculate the total number of cows and return.