LeetCode 299 Bulls and Cows

输入: secret = "1807", guess = "7810"

输出: "1A3B"

说明: 1 个公牛和 3 个奶牛. 公牛是 8, 奶牛是 0, 1 和 7.

输入: secret = "1123", guess = "0111"

输出: "1A1B"

说明: The 1st 1 in friend's guess is a bull, the 2nd or 3rd 1 is a cow.

public String getHint(String secret, String guess) {
    int[] table = new int[10];
    
    int total = 0;
    int bulls = 0;
    for (char c :secret.toCharArray()) {
        table[c - '0']++;
    }

    for (int i = 0; i < guess.length(); i++) {
        if (secret.charAt(i) == guess.charAt(i)) {
            bulls++;
        }
        if (table[guess.charAt(i) - '0']-- > 0) {
            total++;
        }
    }
    
    return bulls + "A" + (total - bulls)  + "B";
}