diff --git a/Sorts/insertionSort.js b/Sorts/insertionSort.js new file mode 100644 index 000000000..1fca84997 --- /dev/null +++ b/Sorts/insertionSort.js @@ -0,0 +1,24 @@ +/*In insertion sort, we divide the initial unsorted array into two parts; +* sorted part and unsorted part. Initially the sorted part just has one +* element (Array of only 1 element is a sorted array). We then pick up +* element one by one from unsorted part; insert into the sorted part at +* the correct position and expand sorted part one element at a time. +*/ +function insertionSort(unsortedList) { + var len = unsortedList.length; + for (var i = 1; i < len; i++) { + var tmp = unsortedList[i]; //Copy of the current element. + /*Check through the sorted part and compare with the number in tmp. If large, shift the number*/ + for (var j = i - 1; j >= 0 && (unsortedList[j] > tmp); j--) { + //Shift the number + unsortedList[j + 1] = unsortedList[j]; + } + //Insert the copied number at the correct position + //in sorted part. + unsortedList[j + 1] = tmp; + } +} + +var arr = [5, 3, 1, 2, 4, 8, 3, 8]; +insertionSort(arr); +console.log(arr);