Data update

Task/List-comprehensions/JavaScript/list-comprehensions-6.js

@@ -0,0 +1,35 @@
+(() => {
+    "use strict";
+
+    // [(x, y, z) | x <- [1..n], y <- [x..n], z <- [y..n], x ^ 2 + y ^ 2 == z ^ 2]
+
+    const main = () => {
+        const n = 20;
+
+        return enumFromTo(1)(n).flatMap(
+            x => enumFromTo(x)(n).flatMap(
+                y => enumFromTo(y)(n).flatMap(
+                    z => x ** 2 + y ** 2 === z ** 2
+                        ? [[x, y, z]]
+                        : []
+                )
+            )
+        );
+    };
+
+
+
+    // --------------------- GENERIC ---------------------
+
+    // enumFromTo :: Int -> Int -> [Int]
+    const enumFromTo = m =>
+        // Enumeration of the integers from m to n.
+        n => Array.from(
+            { length: 1 + n - m },
+            (_, i) => m + i
+        );
+
+
+    // MAIN ---
+    return JSON.stringify(main());
+})();