move mergeTwoSortedArrays to separate file

database/qbreader/get-frequency-list.js

@@ -1,50 +1,6 @@
 import { bonuses, tossups } from './collections.js';
-
 import { DIFFICULTIES } from '../../constants.js';
-
-/**
- * Merge two sorted arrays into a single sorted array.
- * The two arrays should be sorted by the key function.
- * @template T
- * @param {T[]} array1
- * @param {T[]} array2
- * @param {(arg: T) => number} keyFunction - the function to extract the key from each element.
- * @param {(arg1: T, arg2: T) => T} combineFunction - the function to combine two elements with the same key.
- * @returns {T[]} The merged array.
- */
-function mergeTwoSortedArrays (array1, array2, keyFunction, combineFunction) {
-  const mergedArray = [];
-  let i = 0;
-  let j = 0;
-
-  while (i < array1.length && j < array2.length) {
-    const key1 = keyFunction(array1[i]);
-    const key2 = keyFunction(array2[j]);
-    if (key1 < key2) {
-      mergedArray.push(array1[i]);
-      i++;
-    } else if (key1 > key2) {
-      mergedArray.push(array2[j]);
-      j++;
-    } else {
-      mergedArray.push(combineFunction(array1[i], array2[j]));
-      i++;
-      j++;
-    }
-  }
-
-  while (i < array1.length) {
-    mergedArray.push(array1[i]);
-    i++;
-  }
-
-  while (j < array2.length) {
-    mergedArray.push(array2[j]);
-    j++;
-  }
-
-  return mergedArray;
-}
+import mergeTwoSortedArrays from '../../merge-two-sorted-arrays.js';
 
 /**
  * Get a frequency list of answers for a given subcategory and difficulty.

merge-two-sorted-arrays.js

@@ -0,0 +1,43 @@
+/**
+ * Merge two sorted arrays into a single sorted array.
+ * The two arrays should be sorted by the key function.
+ * @template T
+ * @param {T[]} array1
+ * @param {T[]} array2
+ * @param {(arg: T) => number} keyFunction - the function to extract the key from each element.
+ * @param {(arg1: T, arg2: T) => T} combineFunction - the function to combine two elements with the same key.
+ * @returns {T[]} The merged array.
+ */
+export default function mergeTwoSortedArrays (array1, array2, keyFunction, combineFunction) {
+  const mergedArray = [];
+  let i = 0;
+  let j = 0;
+
+  while (i < array1.length && j < array2.length) {
+    const key1 = keyFunction(array1[i]);
+    const key2 = keyFunction(array2[j]);
+    if (key1 < key2) {
+      mergedArray.push(array1[i]);
+      i++;
+    } else if (key1 > key2) {
+      mergedArray.push(array2[j]);
+      j++;
+    } else {
+      mergedArray.push(combineFunction(array1[i], array2[j]));
+      i++;
+      j++;
+    }
+  }
+
+  while (i < array1.length) {
+    mergedArray.push(array1[i]);
+    i++;
+  }
+
+  while (j < array2.length) {
+    mergedArray.push(array2[j]);
+    j++;
+  }
+
+  return mergedArray;
+}