{ "data": { "question": { "questionId": "3181", "questionFrontendId": "2940", "boundTopicId": null, "title": "Find Building Where Alice and Bob Can Meet", "titleSlug": "find-building-where-alice-and-bob-can-meet", "content": "

You are given a 0-indexed array heights of positive integers, where heights[i] represents the height of the ith building.

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If a person is in building i, they can move to any other building j if and only if i < j and heights[i] < heights[j].

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You are also given another array queries where queries[i] = [ai, bi]. On the ith query, Alice is in building ai while Bob is in building bi.

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Return an array ans where ans[i] is the index of the leftmost building where Alice and Bob can meet on the ith query. If Alice and Bob cannot move to a common building on query i, set ans[i] to -1.

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Example 1:

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\nInput: heights = [6,4,8,5,2,7], queries = [[0,1],[0,3],[2,4],[3,4],[2,2]]\nOutput: [2,5,-1,5,2]\nExplanation: In the first query, Alice and Bob can move to building 2 since heights[0] < heights[2] and heights[1] < heights[2]. \nIn the second query, Alice and Bob can move to building 5 since heights[0] < heights[5] and heights[3] < heights[5]. \nIn the third query, Alice cannot meet Bob since Alice cannot move to any other building.\nIn the fourth query, Alice and Bob can move to building 5 since heights[3] < heights[5] and heights[4] < heights[5].\nIn the fifth query, Alice and Bob are already in the same building.  \nFor ans[i] != -1, It can be shown that ans[i] is the leftmost building where Alice and Bob can meet.\nFor ans[i] == -1, It can be shown that there is no building where Alice and Bob can meet.\n
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Example 2:

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\nInput: heights = [5,3,8,2,6,1,4,6], queries = [[0,7],[3,5],[5,2],[3,0],[1,6]]\nOutput: [7,6,-1,4,6]\nExplanation: In the first query, Alice can directly move to Bob's building since heights[0] < heights[7].\nIn the second query, Alice and Bob can move to building 6 since heights[3] < heights[6] and heights[5] < heights[6].\nIn the third query, Alice cannot meet Bob since Bob cannot move to any other building.\nIn the fourth query, Alice and Bob can move to building 4 since heights[3] < heights[4] and heights[0] < heights[4].\nIn the fifth query, Alice can directly move to Bob's building since heights[1] < heights[6].\nFor ans[i] != -1, It can be shown that ans[i] is the leftmost building where Alice and Bob can meet.\nFor ans[i] == -1, It can be shown that there is no building where Alice and Bob can meet.\n\n
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Constraints:

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heights: List[int]\n :type queries: List[List[int]]\n :rtype: List[int]\n \"\"\"\n ", "__typename": "CodeSnippetNode" }, { "lang": "Python3", "langSlug": "python3", "code": "class Solution:\n def leftmostBuildingQueries(self, heights: List[int], queries: List[List[int]]) -> List[int]:\n ", "__typename": "CodeSnippetNode" }, { "lang": "C", "langSlug": "c", "code": "/**\n * Note: The returned array must be malloced, assume caller calls free().\n */\nint* leftmostBuildingQueries(int* heights, int heightsSize, int** queries, int queriesSize, int* queriesColSize, int* returnSize) {\n \n}", "__typename": "CodeSnippetNode" }, { "lang": "C#", "langSlug": "csharp", "code": "public class Solution {\n public int[] LeftmostBuildingQueries(int[] heights, int[][] queries) {\n \n }\n}", "__typename": "CodeSnippetNode" }, { "lang": "JavaScript", "langSlug": "javascript", "code": "/**\n * @param {number[]} heights\n * @param {number[][]} queries\n * @return {number[]}\n */\nvar leftmostBuildingQueries 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leftmostBuildingQueries(List heights, List> queries) {\n \n }\n}", "__typename": "CodeSnippetNode" }, { "lang": "Go", "langSlug": "golang", "code": "func leftmostBuildingQueries(heights []int, queries [][]int) []int {\n \n}", "__typename": "CodeSnippetNode" }, { "lang": "Ruby", "langSlug": "ruby", "code": "# @param {Integer[]} heights\n# @param {Integer[][]} queries\n# @return {Integer[]}\ndef leftmost_building_queries(heights, queries)\n \nend", "__typename": "CodeSnippetNode" }, { "lang": "Scala", "langSlug": "scala", "code": "object Solution {\n def leftmostBuildingQueries(heights: Array[Int], queries: Array[Array[Int]]): Array[Int] = {\n \n }\n}", "__typename": "CodeSnippetNode" }, { "lang": "Rust", "langSlug": "rust", "code": "impl Solution {\n pub fn leftmost_building_queries(heights: Vec, queries: Vec>) -> Vec {\n \n }\n}", "__typename": "CodeSnippetNode" }, { "lang": "Racket", "langSlug": "racket", "code": "(define/contract (leftmost-building-queries heights queries)\n (-> 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Iterate over the queries while maintaining a monotonic stack which we can binary search over to find index t." ], "solution": null, "status": null, "sampleTestCase": "[6,4,8,5,2,7]\n[[0,1],[0,3],[2,4],[3,4],[2,2]]", "metaData": "{\n \"name\": \"leftmostBuildingQueries\",\n \"params\": [\n {\n \"name\": \"heights\",\n \"type\": \"integer[]\"\n },\n {\n \"type\": \"integer[][]\",\n \"name\": \"queries\"\n }\n ],\n \"return\": {\n \"type\": \"integer[]\"\n }\n}", "judgerAvailable": true, "judgeType": "large", "mysqlSchemas": [], "enableRunCode": true, "enableTestMode": false, "enableDebugger": true, "envInfo": "{\"cpp\": [\"C++\", \"

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