Restyle Merge sort in js (#60)

* Merge sort in js * Added test case of merge sort * Restyled by clang-format * Restyled by prettier Co-authored-by: kheenvraj <[email protected]> Co-authored-by: Restyled.io <[email protected]>
nikochiko · Oct 23, 2020 · f9a5b9c · f9a5b9c
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diff --git a/Sorting/merge_sort/merge_sort.js b/Sorting/merge_sort/merge_sort.js
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+/**
+ *  @param {Array} arr Input array.
+ *  @return {Array} Sorted array.
+ * @description Merge sort algorithm in JS.
+ */
+
+module.exports = {
+  mergeSort: (arr) => {
+    var len = arr.length;
+    if (len < 2) return arr;
+    var mid = Math.floor(len / 2),
+      left = arr.slice(0, mid),
+      right = arr.slice(mid);
+    // send left and right to the mergeSort to broke it down into pieces
+    // then merge those
+    return merge(mergeSort(left), mergeSort(right));
+  },
+};
+
+function merge(left, right) {
+  var result = [],
+    lLen = left.length,
+    rLen = right.length,
+    l = 0,
+    r = 0;
+  while (l < lLen && r < rLen) {
+    if (left[l] < right[r]) {
+      result.push(left[l++]);
+    } else {
+      result.push(right[r++]);
+    }
+  }
+  // remaining part needs to be addred to the result
+  return result.concat(left.slice(l)).concat(right.slice(r));
+}
diff --git a/Sorting/merge_sort/merge_sort.test.js b/Sorting/merge_sort/merge_sort.test.js
@@ -0,0 +1,6 @@
+// Test case of merge sort function.
+const merge_sort_test = require("./merge_sort.js");
+
+const input = [5345, 55, 3423, 5346, 33];
+const sorted = merge_sort_test.mergeSort(input);
+console.log("Merge sort", sorted);