a

Makefile

@@ -11,4 +11,8 @@ lint:
 	npx eslint .
 
 brain-even:
-	node bin/brain-even.js
+	node bin/brain-even.js
+
+brain-calc:
+	node bin/brain-calc.js
+

bin/brain-calc.js

@@ -0,0 +1,5 @@
+#!/usr/bin/env node
+
+import calcGame from '../src/calc.js';
+
+calcGame();

src/calc.js

@@ -0,0 +1,38 @@
+import readlineSync from 'readline-sync';
+
+import greetGamer from './cli.js';
+
+const isRightAnswer = (numberOne, numberTwo, operator) => {
+  switch (operator) {
+    case '+':
+      return numberOne + numberTwo;
+    case '-':
+      return numberOne - numberTwo;
+    case '*':
+      return numberOne * numberTwo;
+    default:
+      break;
+  }
+};
+
+const calcGame = () => {
+  for (let i = 0; i < 3; i += 1) {
+    const userName = greetGamer();
+    console.log('What is the result of the expression?');
+    const numberOne = Math.floor(Math.random() * 100);
+    const numberTwo = Math.floor(Math.random() * 100);
+    const operator = '+' || '-' || '*';
+    const expression = `${numberOne} ${operator} ${numberTwo}`;
+    console.log('Question: ', expression);
+    const answerCorrect = isRightAnswer(numberOne, numberTwo, operator);
+    const answerUser = readlineSync.question('Your answer: ');
+    if (answerUser !== answerCorrect) {
+      console.log(`'${answerUser}' is wrong answer ;(. Correct answer was '${answerCorrect}'.`);
+      console.log("Let's try again, ", userName);
+      return;
+    }
+    console.log('Correct!');
+  }
+  console.log('Congratulations,', userName, '!');
+};
+export default calcGame;