add solution

src/app.js

@@ -1 +1,39 @@
+/* eslint-disable no-console */
 'use strict';
+
+const { generateRandomNumber } = require('./generateRandomNumber');
+const { calculateBullsAndCows } = require('./calculateBullsAndCows');
+const { getUserInput, closeInterface } = require('./getUserInput');
+
+(async () => {
+  const secretNumber = generateRandomNumber();
+
+  console.log('Welcome to Bulls and Cows game!');
+
+  let attempts = 0;
+
+  while (true) {
+    const guess = await getUserInput('Enter your guess (4 different digits): ');
+
+    console.log(`Your guess:  ${guess}`);
+
+    if (new Set(guess).size !== 4 || isNaN(guess)) {
+      console.log('Invalid input. Please enter 4 different digits.');
+      continue;
+    }
+
+    attempts++;
+
+    const result = calculateBullsAndCows(secretNumber, guess);
+
+    console.log(`Bulls: ${result.bulls}, Cows: ${result.cows}`);
+
+    if (result.bulls === 4) {
+      console.log(
+        `Congratulations! You guessed the number in ${attempts} attempts.`
+      );
+      closeInterface();
+      break;
+    }
+  }
+})();

src/calculateBullsAndCows.js

@@ -0,0 +1,21 @@
+'use strict';
+
+function calculateBullsAndCows(secretNumber, guess) {
+  let bulls = 0;
+  let cows = 0;
+
+  for (let i = 0; i < secretNumber.length; i++) {
+    if (secretNumber[i] === guess[i]) {
+      bulls++;
+    } else if (secretNumber.includes(guess[i])) {
+      cows++;
+    }
+  }
+
+  return {
+    bulls,
+    cows,
+  };
+}
+
+module.exports = { calculateBullsAndCows };

src/generateRandomNumber.js

@@ -0,0 +1,17 @@
+'use strict';
+
+function generateRandomNumber() {
+  const digits = [];
+
+  while (digits.length < 4) {
+    const randomNumber = Math.floor(Math.random() * 10);
+
+    if (!digits.includes(randomNumber)) {
+      digits.push(randomNumber);
+    }
+  }
+
+  return digits.join('');
+}
+
+module.exports = { generateRandomNumber };

src/getUserInput.js

@@ -0,0 +1,26 @@
+/* eslint-disable no-console */
+'use strict';
+
+const readline = require('readline');
+
+const terminal = readline.createInterface({
+  input: process.stdin,
+  output: process.stdout,
+});
+
+function getUserInput(prompt) {
+  return new Promise((resolve) => {
+    terminal.question(prompt, (answer) => {
+      resolve(answer);
+    });
+  });
+}
+
+function closeInterface() {
+  terminal.close();
+}
+
+module.exports = {
+  getUserInput,
+  closeInterface,
+};