What is between - in JS, TS

Author: a-merezhanyi

8kyu/(8 kyu) What is between/(8 kyu) What is between.js

@@ -0,0 +1,23 @@
+// 1 Plain solution
+function between(a, b) {
+    const res = [];
+
+    for (let i = a; i <= b; i++) {
+        res.push(i);
+    }
+
+    return res;
+}
+
+// 2 Optimized solution
+function between(a, b) {
+    const res = Array(b - a + 1).fill(0);
+    return res.map((_, i) => a + i);
+}
+
+// 3 Clever solution
+const between = (a, b) =>
+    Array.from(
+        new Array(b - a + 1),
+        (_, i) => a + i
+    );

8kyu/(8 kyu) What is between/(8 kyu) What is between.md

@@ -0,0 +1,11 @@
+# What is between (8 kyu)
+
+Complete the function that takes two integers (a, b, where a < b) and return an array of all integers between the input parameters, including them.
+
+For example:
+
+```
+a = 1
+b = 4
+--> [1, 2, 3, 4]
+```

8kyu/(8 kyu) What is between/(8 kyu) What is between.ts

@@ -0,0 +1,4 @@
+export function between(a: number, b: number): number[] {
+    const res = Array(b - a + 1).fill(0);
+    return res.map((_, i) => a + i);
+}

README.md

@@ -660,7 +660,7 @@ JS Video Tutorial) :
 / [[Java](<7kyu/(7%20kyu)%20Two%20to%20One/(7%20kyu)%20Two%20to%20One.java>)]
 / [[Go](<7kyu/(7%20kyu)%20Two%20to%20One/(7%20kyu)%20Two%20to%20One.go>)]
 
-## 8 kyu Katas (49 -> 55)
+## 8 kyu Katas (50 -> 55)
 
 **[(8 kyu) Abbreviate a Two Word Name](https://www.codewars.com/kata/abbreviate-a-two-word-name)**
 ([Description](<8kyu/(8%20kyu)%20Abbreviate%20a%20Two%20Word%20Name/(8%20kyu)%20Abbreviate%20a%20Two%20Word%20Name.md>) +
@@ -1214,6 +1214,17 @@ JS Video Tutorial) :
 / [Java]
 / [Go]
 <br>
+**[(8 kyu) What is between](https://www.codewars.com/kata/55ecd718f46fba02e5000029/)** ([Description](<8kyu/(8%20kyu)%20What%20is%20between/(8%20kyu)%20What%20is%20between.md>) +
+JS Video Tutorial) :
+[[JavaScript](<8kyu/(8%20kyu)%20What%20is%20between/(8%20kyu)%20What%20is%20between.js>)]
+/ [[TypeScript](<8kyu/(8%20kyu)%20What%20is%20between/(8%20kyu)%20What%20is%20between.ts>)]
+/ [Python]
+/ [Rust]
+/ [C++]
+/ [C#]
+/ [Java]
+/ [Go]
+<br>
 **[(8 kyu) You Can't Code Under Pressure #1](https://www.codewars.com/kata/53ee5429ba190077850011d4/)** ([Description](<8kyu/(8%20kyu)%20You%20Cant%20Code%20Under%20Pressure%201/(8%20kyu)%20You%20Cant%20Code%20Under%20Pressure%201.md>) +
 JS Video Tutorial) :
 [[JavaScript](<8kyu/(8%20kyu)%20You%20Cant%20Code%20Under%20Pressure%201/(8%20kyu)%20You%20Cant%20Code%20Under%20Pressure%201.js>)]