Bull and cows

Package cn.edu.xidian.sselab.hashtable; Import Java.util.HashMap; Import Java.util.Map; Import Java.util.Set; /** * * @author Zhiyong Wang * Title:bull and cows * Content: * OU is playing the following Bulls and cows game with your friend:you write off a number and ask your friend to guess What's the number is. Each time your friend makes a guess, you provide a hint the indicates how many digits in said guess match your secret num ber exactly in both digit and position (called "bulls") and how many digits match the secret number but locate in the Wron G position (called "cows"). Your Friend would use successive guesses and hints to eventually derive the secret number. * For example: * * Secret Number: "1807" * Friend ' s guess: "7810" * * Hint:1 Bull and 3 cows. (The bull is 8, the cows is 0, 1 and 7.) * * Write a function to return a hint according to the secret number and friend's guess, use a to indicate the Bulls and B t o indicate the cows. In the above example, your function should return "1a3b". * * Please note that both secret number and friend's guess may contain duplicate digits, for example: * * Secret Number: "1123" * Friend ' s guess: "0111" * The 1st 1 in friend's guess is a bull, the 2nd or 3rd 1 is a cow, and your function should return "1A1B". * * May assume the secret number and your friend's guess only contain digits, and their lengths is always equal. * */ public class Bullandcows { I did not think of it, refer to Daniel's problem-solving ideas Here the default secret is equal to the length of guess This place. The value of cow is to save 0 to 9 by creating a new array of 10 numbers, the initialization value is 0, if in secret, his corresponding value plus 1, if in guess, his corresponding value minus 1 This way, if the value of a bit in the secret is displayed in the array less than 0, it means that he has previously appeared in Guess, through guess. public string Gethint (String secret, String guess) { int[] numbers = new INT[10]; int bull = 0; int cow = 0; if (secret = = NULL | | guess = NULL) return null; if (secret.length () = = 0 | | guess.length () = = 0) return "0a0b"; for (int i=0;i<secret.length (); i++) { if (Secret.charat (i) = = Guess.charat (i)) bull++; else{ if (Numbers[secret.charat (i)-' 0 ']++ < 0) cow++; if (Numbers[guess.charat (i)-' 0 ']--> 0) cow++; } } return bull + "A" + Cow + "B"; } } ?

Bull and cows