Add new game brain-progression

Author: root

Makefile

@@ -8,6 +8,8 @@ brain-calc:
 	node bin/brain-calc.js
 brain-gcd:
 	node bin/brain-gcd.js
+brain-progression:
+	node bin/brain-progression.js
 publish:
 	npm publish --dry-run
 lint:

bin/brain-progression.js

@@ -0,0 +1,5 @@
+#!/usr/bin/env node
+
+import gamePRG from "../src/brainPGRESS.js";
+
+gamePRG();

package.json

@@ -8,7 +8,8 @@
     "brain-games": "bin/brain-games.js",
     "brain-even": "bin/brain-even.js",
     "brain-calc": "bin/brain-calc.js",
-    "brain-gcd": "bin/brain-gcd.js"
+    "brain-gcd": "bin/brain-gcd.js",
+    "brain-progression": "bin/brain-progression.js"
   },
   "scripts": {
     "test": "echo \"Error: no test specified\" && exit 1"

src/brainPGRESS.js

@@ -0,0 +1,27 @@
+import { getRandomNum } from "./brainEven.js";
+import { TheMotor } from "../index.js";
+const genPRG = (length, firstElem, prgStep)=>{
+    const progression = [];
+    for (let i = 0; i < length; i += 1) {
+        progression.push(firstElem + prgStep * i);
+    }
+    return progression;
+}
+const alert = "What number is missing in the progression?";
+const genRounds = () =>{
+    const progressionLength = 10;
+    const firstElem = getRandomNum(1, 10);
+    const prgStep = getRandomNum(2,10);
+    const progression = genPRG(progressionLength, firstElem, prgStep);
+    const indexOfHide = getRandomNum(0, progressionLength - 1);
+    const hiddenElem = progression[indexOfHide];
+    progression[indexOfHide] = "..";
+    const question = progression.join(" ");
+    const rightAnswer = hiddenElem.toString();
+    return [question, rightAnswer];
+
+}
+const gamePRG = () =>{
+    TheMotor(alert, genRounds);
+}
+export default gamePRG;