https://leetcode.cn/problems/distance-between-bus-stops/

Author: masx200

README.md

@@ -886,6 +886,8 @@ https://leetcode.cn/problems/o8SXZn
 
 https://leetcode.cn/problems/insert-delete-getrandom-o1-duplicates-allowed/
 
+https://leetcode.cn/problems/distance-between-bus-stops/
+
 https://leetcode.cn/problems/find-median-from-data-stream/
 
 https://leetcode.cn/problems/replace-words/

deps.ts

@@ -22,3 +22,5 @@ export {
     BinarySearchTree,
     BinarySearchTreeNode,
 } from "https://cdn.skypack.dev/@datastructures-js/[email protected]/index.js?dts";
+export { default as groupBy } from "https://cdn.skypack.dev/[email protected]/groupBy?dts";
+export { default as sum } from "https://cdn.skypack.dev/[email protected]/sum?dts";

distance-between-bus-stops/index.ts

@@ -0,0 +1,25 @@
+function distanceBetweenBusStops(
+    distance: number[],
+    start: number,
+    destination: number,
+): number {
+    [start, destination] = [
+        Math.min(start, destination),
+        Math.max(start, destination),
+    ];
+
+    return Math.min(
+        // deno-lint-ignore ban-ts-comment
+        //@ts-ignore
+        ...Object.values(
+            groupBy(
+                Array.from(distance.entries()),
+                ([index]) => start <= index && index < destination,
+            ),
+            // deno-lint-ignore ban-ts-comment
+            //@ts-ignore
+        ).map((value) => sum(value.map((a) => a[1]))),
+    );
+}
+export default distanceBetweenBusStops;
+import { groupBy, sum } from "../deps.ts";

distance-between-bus-stops/test.ts

@@ -0,0 +1,30 @@
+import { assertEquals } from "../deps.ts";
+import distanceBetweenBusStops from "./index.ts";
+
+Deno.test("distance-between-bus-stops", () => {
+    const distance = [1, 2, 3, 4];
+    const start = 0;
+    const destination = 3;
+    const expected = 4;
+    const actual = distanceBetweenBusStops(distance, start, destination);
+    assertEquals(actual, expected);
+
+    const distance2 = [1, 2, 3, 4];
+    const start2 = 0;
+    const destination2 = 2;
+    const expected2 = 3;
+    const actual2 = distanceBetweenBusStops(distance2, start2, destination2);
+    assertEquals(actual2, expected2);
+
+    const distance3 = [1, 2, 3, 4];
+    const start3 = 0;
+    const destination3 = 1;
+    const expected3 = 1;
+
+    const actual3 = distanceBetweenBusStops(distance3, start3, destination3);
+    assertEquals(actual3, expected3);
+    assertEquals(
+        distanceBetweenBusStops([7, 10, 1, 12, 11, 14, 5, 0], 7, 2),
+        17,
+    );
+});