📦 NEW: Add Selection sort

ephremdeme · ephremdeme · commit ee387c333c32 · 2020-09-25T19:15:42.000+03:00
Selection sort algorithm implementation in javascript
diff --git a/Sorts/selectionSort.js b/Sorts/selectionSort.js
@@ -0,0 +1,30 @@
+/*
+
+Selection sort is fairly simple. Assume the left part of your array is
+sorted and right part is unsorted. Inititally the sorted(left) part is
+empty. Now select the smallest element from the unsorted(right) part and
+swap it with the first element of the unsorted(right) part. Now this element
+is sorted, move to the next iteration and repeat without touch the sorted(left)
+part.
+
+*/
+function selectionSort(arr) {
+  for (let i = 0; i < arr.length; i++) {
+    let firstOfUnsorted = arr[i];
+
+    // find the index of the smallest element in the unsorted part
+    let minIndex = i;
+    for (let j = i + 1; j < arr.length; j++) {
+      if (arr[minIndex] > arr[j]) {
+        minIndex = j;
+      }
+    }
+
+    // swapping the minimum with first element of unsorted part
+    arr[i] = arr[minIndex];
+    arr[minIndex] = firstOfUnsorted;
+  }
+  return arr;
+}
+
+// This has the time complexity of O(n^2)
