[solution] insertion sort for string

lib/insertionsort.ts

@@ -0,0 +1,49 @@
+const STR = "insertionsort";
+const SORT_STR = "eiinnoorrsstt";
+const NUMB = [12, -2, 55, 68, 80];
+const SORT_NUMB = [-2, 12, 55, 68, 80];
+
+function swapCharsInString(str: string, i: number, j: number) {
+  return (
+    str.substring(0, i) +
+    str[j] +
+    str.substring(i + 1, j) +
+    str[i] +
+    str.substring(j + 1)
+  );
+}
+
+const swapElements = (arr: number[], index1: number, index2: number) => {
+  [arr[index1], arr[index2]] = [arr[index2], arr[index1]];
+};
+
+export function insertionSort(str: string): string;
+export function insertionSort(arr: number[]): number[];
+
+export function insertionSort(sortItems: string | number[]) {
+  let L: number, R: number;
+
+  for (L = 1; L < sortItems.length; L++) {
+    R = L;
+
+    while (R > 0 && sortItems[R] < sortItems[R - 1]) {
+      const index1 = R;
+      const index2 = R - 1;
+
+      if (typeof sortItems === "string") {
+        sortItems = swapCharsInString(sortItems, index2, index1);
+      }
+
+      if (Array.isArray(sortItems)) {
+        swapElements(sortItems, index1, index2);
+      }
+
+      R = R - 1;
+    }
+  }
+
+  return sortItems;
+}
+
+console.log(insertionSort(STR), SORT_STR);
+console.log(insertionSort(NUMB), SORT_NUMB);