题目：

题解：

func getHint(secret, guess string) string {     bulls := 0     var cntS, cntG [10]int     for i := range secret {         if secret[i] == guess[i] {             bulls++         } else {             cntS[secret[i]-'0']++             cntG[guess[i]-'0']++         }     }     cows := 0     for i := 0; i < 10; i++ {         cows += min(cntS[i], cntG[i])     }     return fmt.Sprintf("%dA%dB", bulls, cows) }  func min(a, b int) int {     if a > b {         return b     }     return a }