{ "data": { "question": { "questionId": "803", "questionFrontendId": "787", "categoryTitle": "Algorithms", "boundTopicId": 1893, "title": "Cheapest Flights Within K Stops", "titleSlug": "cheapest-flights-within-k-stops", "content": "

There are n cities connected by some number of flights. You are given an array flights where flights[i] = [fromi, toi, pricei] indicates that there is a flight from city fromi to city toi with cost pricei.

\n\n

You are also given three integers src, dst, and k, return the cheapest price from src to dst with at most k stops. If there is no such route, return -1.

\n\n

 

\n

Example 1:

\n\"\"\n
\nInput: n = 4, flights = [[0,1,100],[1,2,100],[2,0,100],[1,3,600],[2,3,200]], src = 0, dst = 3, k = 1\nOutput: 700\nExplanation:\nThe graph is shown above.\nThe optimal path with at most 1 stop from city 0 to 3 is marked in red and has cost 100 + 600 = 700.\nNote that the path through cities [0,1,2,3] is cheaper but is invalid because it uses 2 stops.\n
\n\n

Example 2:

\n\"\"\n
\nInput: n = 3, flights = [[0,1,100],[1,2,100],[0,2,500]], src = 0, dst = 2, k = 1\nOutput: 200\nExplanation:\nThe graph is shown above.\nThe optimal path with at most 1 stop from city 0 to 2 is marked in red and has cost 100 + 100 = 200.\n
\n\n

Example 3:

\n\"\"\n
\nInput: n = 3, flights = [[0,1,100],[1,2,100],[0,2,500]], src = 0, dst = 2, k = 0\nOutput: 500\nExplanation:\nThe graph is shown above.\nThe optimal path with no stops from city 0 to 2 is marked in red and has cost 500.\n
\n\n

 

\n

Constraints:

\n\n\n", "translatedTitle": "K 站中转内最便宜的航班", "translatedContent": "

有 n 个城市通过一些航班连接。给你一个数组 flights ，其中 flights[i] = [fromi, toi, pricei] ，表示该航班都从城市 fromi 开始，以价格 pricei 抵达 toi。

\n\n

现在给定所有的城市和航班，以及出发城市 src 和目的地 dst，你的任务是找到出一条最多经过 k 站中转的路线，使得从 src 到 dst 的 价格最便宜 ，并返回该价格。 如果不存在这样的路线，则输出 -1。

\n\n

 

\n\n

示例 1：

\n\n
\n输入: \nn = 3, edges = [[0,1,100],[1,2,100],[0,2,500]]\nsrc = 0, dst = 2, k = 1\n输出: 200\n解释: \n城市航班图如下\n\"\"\n\n从城市 0 到城市 2 在 1 站中转以内的最便宜价格是 200，如图中红色所示。
\n\n

示例 2：

\n\n
\n输入: \nn = 3, edges = [[0,1,100],[1,2,100],[0,2,500]]\nsrc = 0, dst = 2, k = 0\n输出: 500\n解释: \n城市航班图如下\n\"\"\n\n从城市 0 到城市 2 在 0 站中转以内的最便宜价格是 500，如图中蓝色所示。
\n\n

 

\n\n

提示：

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Solution(object):\n def findCheapestPrice(self, n, flights, src, dst, k):\n \"\"\"\n :type n: int\n :type flights: List[List[int]]\n :type src: int\n :type dst: int\n :type k: int\n :rtype: int\n \"\"\"", "__typename": "CodeSnippetNode" }, { "lang": "Python3", "langSlug": "python3", "code": "class Solution:\n def findCheapestPrice(self, n: int, flights: List[List[int]], src: int, dst: int, k: int) -> int:", "__typename": "CodeSnippetNode" }, { "lang": "C", "langSlug": "c", "code": "\n\nint findCheapestPrice(int n, int** flights, int flightsSize, int* flightsColSize, int src, int dst, int k){\n\n}", "__typename": "CodeSnippetNode" }, { "lang": "C#", "langSlug": "csharp", "code": "public class Solution {\n public int FindCheapestPrice(int n, int[][] flights, int src, int dst, int k) {\n\n }\n}", "__typename": "CodeSnippetNode" }, { "lang": "JavaScript", "langSlug": "javascript", "code": "/**\n * @param {number} n\n * @param {number[][]} flights\n * @param {number} src\n * @param {number} dst\n * @param {number} k\n * @return {number}\n */\nvar findCheapestPrice = function(n, flights, src, dst, k) {\n\n};", "__typename": "CodeSnippetNode" }, { "lang": "Ruby", "langSlug": "ruby", "code": "# @param {Integer} n\n# @param {Integer[][]} flights\n# @param {Integer} src\n# @param {Integer} dst\n# @param {Integer} k\n# @return {Integer}\ndef find_cheapest_price(n, flights, src, dst, k)\n\nend", "__typename": "CodeSnippetNode" }, { "lang": "Swift", "langSlug": "swift", "code": "class Solution {\n func findCheapestPrice(_ n: Int, _ flights: [[Int]], _ src: Int, _ dst: Int, _ k: Int) -> Int {\n\n }\n}", "__typename": "CodeSnippetNode" }, { "lang": "Go", "langSlug": "golang", "code": "func findCheapestPrice(n int, flights [][]int, src int, dst int, k int) int {\n\n}", "__typename": "CodeSnippetNode" }, { "lang": "Scala", "langSlug": "scala", "code": "object Solution {\n def findCheapestPrice(n: Int, flights: Array[Array[Int]], src: Int, dst: Int, k: Int): Int = {\n\n }\n}", 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