Search⌘ K
AI Features
Home
Courses
Grokking the Coding Interview Patterns in C#

Solution: Bulls and Cows

Explore how to implement a Bulls and Cows solution that counts digits correctly placed (bulls) and digits in the wrong position (cows) using hash maps. Understand the single pass method for counting unmatched digits, optimizing time and space complexity in coding challenges.

We'll cover the following...

Statement

You are playing a number guessing game called “Bulls and Cows” with a friend.

You write down a secret number, and your friend tries to guess it. After each guess, you provide a hint based on the following:

  • Bulls: The number of digits that are in the correct position in the guess.

  • Cows: The number of digits that are in both the secret and the guess but in different positions. (These are non-bull digits that could become bulls if rearranged.)

Your task is to return a hint for the guess, formatted as “xAyB”, where:

  • x is the number of bulls.

  • y is the number of cows.

Note: Both the secret number and the guess may contain duplicate digits.

Constraints:

  • 1<=1 <= secret.length, guess.length ...