{ "data": { "question": { "questionId": "3957", "questionFrontendId": "3715", "categoryTitle": "Algorithms", "boundTopicId": 3803257, "title": "Sum of Perfect Square Ancestors", "titleSlug": "sum-of-perfect-square-ancestors", "content": "
You are given an integer n and an undirected tree rooted at node 0 with n nodes numbered from 0 to n - 1. This is represented by a 2D array edges of length n - 1, where edges[i] = [ui, vi] indicates an undirected edge between nodes ui and vi.
You are also given an integer array nums, where nums[i] is the positive integer assigned to node i.
Define a value ti as the number of ancestors of node i such that the product nums[i] * nums[ancestor] is a perfect square.
Return the sum of all ti values for all nodes i in range [1, n - 1].
Note:
\n\ni are all nodes on the path from node i to the root node 0, excluding i itself.\n
Example 1:
\n\nInput: n = 3, edges = [[0,1],[1,2]], nums = [2,8,2]
\n\nOutput: 3
\n\nExplanation:
\n\ni | \n\t\t\tAncestors | \n\t\t\tnums[i] * nums[ancestor] | \n\t\t\tSquare Check | \n\t\t\tti | \n\t\t
|---|---|---|---|---|
| 1 | \n\t\t\t[0] | \n\t\t\tnums[1] * nums[0] = 8 * 2 = 16 | \n\t\t\t16 is a perfect square | \n\t\t\t1 | \n\t\t
| 2 | \n\t\t\t[1, 0] | \n\t\t\tnums[2] * nums[1] = 2 * 8 = 16\n\t\t\t nums[2] * nums[0] = 2 * 2 = 4 | \n\t\t\tBoth 4 and 16 are perfect squares | \n\t\t\t2 | \n\t\t
Thus, the total number of valid ancestor pairs across all non-root nodes is 1 + 2 = 3.
Example 2:
\n\nInput: n = 3, edges = [[0,1],[0,2]], nums = [1,2,4]
\n\nOutput: 1
\n\nExplanation:
\n\ni | \n\t\t\tAncestors | \n\t\t\tnums[i] * nums[ancestor] | \n\t\t\tSquare Check | \n\t\t\tti | \n\t\t
|---|---|---|---|---|
| 1 | \n\t\t\t[0] | \n\t\t\tnums[1] * nums[0] = 2 * 1 = 2 | \n\t\t\t2 is not a perfect square | \n\t\t\t0 | \n\t\t
| 2 | \n\t\t\t[0] | \n\t\t\tnums[2] * nums[0] = 4 * 1 = 4 | \n\t\t\t4 is a perfect square | \n\t\t\t1 | \n\t\t
Thus, the total number of valid ancestor pairs across all non-root nodes is 1.
\nExample 3:
\n\nInput: n = 4, edges = [[0,1],[0,2],[1,3]], nums = [1,2,9,4]
\n\nOutput: 2
\n\nExplanation:
\n\ni | \n\t\t\tAncestors | \n\t\t\tnums[i] * nums[ancestor] | \n\t\t\tSquare Check | \n\t\t\tti | \n\t\t
|---|---|---|---|---|
| 1 | \n\t\t\t[0] | \n\t\t\tnums[1] * nums[0] = 2 * 1 = 2 | \n\t\t\t2 is not a perfect square | \n\t\t\t0 | \n\t\t
| 2 | \n\t\t\t[0] | \n\t\t\tnums[2] * nums[0] = 9 * 1 = 9 | \n\t\t\t9 is a perfect square | \n\t\t\t1 | \n\t\t
| 3 | \n\t\t\t[1, 0] | \n\t\t\tnums[3] * nums[1] = 4 * 2 = 8\n\t\t\t nums[3] * nums[0] = 4 * 1 = 4 | \n\t\t\tOnly 4 is a perfect square | \n\t\t\t1 | \n\t\t
Thus, the total number of valid ancestor pairs across all non-root nodes is 0 + 1 + 1 = 2.
\n
Constraints:
\n\n1 <= n <= 105edges.length == n - 1edges[i] = [ui, vi]0 <= ui, vi <= n - 1nums.length == n1 <= nums[i] <= 105edges represents a valid tree.给你一个整数 n,以及一棵以节点 0 为根、包含 n 个节点(编号从 0 到 n - 1)的无向树。该树由一个长度为 n - 1 的二维数组 edges 表示,其中 edges[i] = [ui, vi] 表示在节点 ui 与节点 vi 之间有一条无向边。
同时给你一个整数数组 nums,其中 nums[i] 是分配给节点 i 的正整数。
定义值 ti 为:节点 i 的 祖先 节点中,满足乘积 nums[i] * nums[ancestor] 为 完全平方数 的祖先个数。
请返回所有节点 i(范围为 [1, n - 1])的 ti 之和。
说明:
\n\ni 的祖先是指从节点 i 到根节点 0 的路径上、不包括 i 本身的所有节点。1、4、9、16。\n\n
示例 1:
\n\n输入: n = 3, edges = [[0,1],[1,2]], nums = [2,8,2]
\n\n输出: 3
\n\n解释:
\n\ni | \n\t\t\t祖先 | \n\t\t\tnums[i] * nums[ancestor] | \n\t\t\t平方数检查 | \n\t\t\tti | \n\t\t
|---|---|---|---|---|
| 1 | \n\t\t\t[0] | \n\t\t\tnums[1] * nums[0] = 8 * 2 = 16 | \n\t\t\t16 是完全平方数 | \n\t\t\t1 | \n\t\t
| 2 | \n\t\t\t[1, 0] | \n\t\t\tnums[2] * nums[1] = 2 * 8 = 16\n\t\t\t nums[2] * nums[0] = 2 * 2 = 4 | \n\t\t\t4 和 16 都是完全平方数 | \n\t\t\t2 | \n\t\t
因此,所有非根节点的有效祖先配对总数为 1 + 2 = 3。
示例 2:
\n\n输入: n = 3, edges = [[0,1],[0,2]], nums = [1,2,4]
\n\n输出: 1
\n\n解释:
\n\ni | \n\t\t\t祖先 | \n\t\t\tnums[i] * nums[ancestor] | \n\t\t\t平方数检查 | \n\t\t\tti | \n\t\t
|---|---|---|---|---|
| 1 | \n\t\t\t[0] | \n\t\t\tnums[1] * nums[0] = 2 * 1 = 2 | \n\t\t\t2 不是 完全平方数 | \n\t\t\t0 | \n\t\t
| 2 | \n\t\t\t[0] | \n\t\t\tnums[2] * nums[0] = 4 * 1 = 4 | \n\t\t\t4 是完全平方数 | \n\t\t\t1 | \n\t\t
因此,所有非根节点的有效祖先配对总数为 1。
\n示例 3:
\n\n输入: n = 4, edges = [[0,1],[0,2],[1,3]], nums = [1,2,9,4]
\n\n输出: 2
\n\n解释:
\n\ni | \n\t\t\t祖先 | \n\t\t\tnums[i] * nums[ancestor] | \n\t\t\t平方数检查 | \n\t\t\tti | \n\t\t
|---|---|---|---|---|
| 1 | \n\t\t\t[0] | \n\t\t\tnums[1] * nums[0] = 2 * 1 = 2 | \n\t\t\t2 不是 完全平方数 | \n\t\t\t0 | \n\t\t
| 2 | \n\t\t\t[0] | \n\t\t\tnums[2] * nums[0] = 9 * 1 = 9 | \n\t\t\t9 是完全平方数 | \n\t\t\t1 | \n\t\t
| 3 | \n\t\t\t[1, 0] | \n\t\t\tnums[3] * nums[1] = 4 * 2 = 8\n\t\t\t nums[3] * nums[0] = 4 * 1 = 4 | \n\t\t\t只有 4 是完全平方数 | \n\t\t\t1 | \n\t\t
因此,所有非根节点的有效祖先配对总数为 0 + 1 + 1 = 2。
\n\n
提示:
\n\n1 <= n <= 105edges.length == n - 1edges[i] = [ui, vi]0 <= ui, vi <= n - 1nums.length == n1 <= nums[i] <= 105edges 表示一棵有效的树。nums[i] * nums[ancestor] is a perfect square if and only if both numbers have the same \"square-free kernel\" (i.e., after removing all even powers of primes, the remaining product is identical).",
"Precompute the square-free representation of every node's value using prime factorization up to max(nums[i]).",
"Perform a DFS from the root. While traversing down the tree, maintain a frequency map of the square-free values of the ancestors.",
"For each node, the number of valid ancestors equals the count of ancestors with the same square-free value.",
"Carefully backtrack the frequency map after finishing a subtree to maintain correctness."
],
"solution": null,
"status": null,
"sampleTestCase": "3\n[[0,1],[1,2]]\n[2,8,2]",
"metaData": "{\n \"name\": \"sumOfAncestors\",\n \"params\": [\n {\n \"name\": \"n\",\n \"type\": \"integer\"\n },\n {\n \"type\": \"integer[][]\",\n \"name\": \"edges\"\n },\n {\n \"type\": \"integer[]\",\n \"name\": \"nums\"\n }\n ],\n \"return\": {\n \"type\": \"long\"\n }\n}",
"judgerAvailable": true,
"judgeType": "large",
"mysqlSchemas": [],
"enableRunCode": true,
"envInfo": "{\"cpp\":[\"C++\",\"\\u7248\\u672c\\uff1a \\u7f16\\u8bd1\\u65f6\\uff0c\\u5c06\\u4f1a\\u91c7\\u7528 \\u4e3a\\u4e86\\u4f7f\\u7528\\u65b9\\u4fbf\\uff0c\\u5927\\u90e8\\u5206\\u6807\\u51c6\\u5e93\\u7684\\u5934\\u6587\\u4ef6\\u5df2\\u7ecf\\u88ab\\u81ea\\u52a8\\u5bfc\\u5165\\u3002<\\/p>\"],\"java\":[\"Java\",\" \\u7248\\u672c\\uff1a \\u4e3a\\u4e86\\u65b9\\u4fbf\\u8d77\\u89c1\\uff0c\\u5927\\u90e8\\u5206\\u6807\\u51c6\\u5e93\\u7684\\u5934\\u6587\\u4ef6\\u5df2\\u88ab\\u5bfc\\u5165\\u3002<\\/p>\\r\\n\\r\\n \\u5305\\u542b Pair \\u7c7b: https:\\/\\/docs.oracle.com\\/javase\\/8\\/javafx\\/api\\/javafx\\/util\\/Pair.html <\\/p>\"],\"python\":[\"Python\",\" \\u7248\\u672c\\uff1a \\u4e3a\\u4e86\\u65b9\\u4fbf\\u8d77\\u89c1\\uff0c\\u5927\\u90e8\\u5206\\u5e38\\u7528\\u5e93\\u5df2\\u7ecf\\u88ab\\u81ea\\u52a8 \\u5bfc\\u5165\\uff0c\\u5982\\uff1aarray<\\/a>, bisect<\\/a>, collections<\\/a>\\u3002\\u5982\\u679c\\u60a8\\u9700\\u8981\\u4f7f\\u7528\\u5176\\u4ed6\\u5e93\\u51fd\\u6570\\uff0c\\u8bf7\\u81ea\\u884c\\u5bfc\\u5165\\u3002<\\/p>\\r\\n\\r\\n \\u6ce8\\u610f Python 2.7 \\u5df2\\u4e0d\\u518d\\u7ef4\\u62a4<\\/a>\\u3002 \\u5982\\u60f3\\u4f7f\\u7528\\u6700\\u65b0\\u7248\\u7684Python\\uff0c\\u8bf7\\u9009\\u62e9Python 3\\u3002<\\/p>\"],\"c\":[\"C\",\" \\u7248\\u672c\\uff1a \\u7f16\\u8bd1\\u65f6\\uff0c\\u5c06\\u4f1a\\u91c7\\u7528 \\u4e3a\\u4e86\\u4f7f\\u7528\\u65b9\\u4fbf\\uff0c\\u5927\\u90e8\\u5206\\u6807\\u51c6\\u5e93\\u7684\\u5934\\u6587\\u4ef6\\u5df2\\u7ecf\\u88ab\\u81ea\\u52a8\\u5bfc\\u5165\\u3002<\\/p>\\r\\n\\r\\n \\u5982\\u60f3\\u4f7f\\u7528\\u54c8\\u5e0c\\u8868\\u8fd0\\u7b97, \\u60a8\\u53ef\\u4ee5\\u4f7f\\u7528 uthash<\\/a>\\u3002 \\\"uthash.h\\\"\\u5df2\\u7ecf\\u9ed8\\u8ba4\\u88ab\\u5bfc\\u5165\\u3002\\u8bf7\\u770b\\u5982\\u4e0b\\u793a\\u4f8b:<\\/p>\\r\\n\\r\\n 1. \\u5f80\\u54c8\\u5e0c\\u8868\\u4e2d\\u6dfb\\u52a0\\u4e00\\u4e2a\\u5bf9\\u8c61\\uff1a<\\/b>\\r\\n 2. \\u5728\\u54c8\\u5e0c\\u8868\\u4e2d\\u67e5\\u627e\\u4e00\\u4e2a\\u5bf9\\u8c61\\uff1a<\\/b>\\r\\n 3. \\u4ece\\u54c8\\u5e0c\\u8868\\u4e2d\\u5220\\u9664\\u4e00\\u4e2a\\u5bf9\\u8c61\\uff1a<\\/b>\\r\\n C# 13<\\/a> \\u8fd0\\u884c\\u5728 .NET 9 \\u4e0a<\\/p>\"],\"javascript\":[\"JavaScript\",\" \\u7248\\u672c\\uff1a \\u60a8\\u7684\\u4ee3\\u7801\\u5728\\u6267\\u884c\\u65f6\\u5c06\\u5e26\\u4e0a lodash.js<\\/a> \\u5e93\\u5df2\\u7ecf\\u9ed8\\u8ba4\\u88ab\\u5305\\u542b\\u3002<\\/p>\\r\\n\\r\\n \\u60a8\\u53ef\\u4f7f\\u7528 datastructures-js <\\/a>\\u5e93\\u6240\\u63d0\\u4f9b\\u7684\\u6570\\u636e\\u7ed3\\u6784\\u3002<\\/p>\"],\"ruby\":[\"Ruby\",\" \\u4f7f\\u7528 \\u4e00\\u4e9b\\u5e38\\u7528\\u7684\\u6570\\u636e\\u7ed3\\u6784\\u5df2\\u5728 Algorithms \\u6a21\\u5757\\u4e2d\\u63d0\\u4f9b\\uff1ahttps:\\/\\/www.rubydoc.info\\/github\\/kanwei\\/algorithms\\/Algorithms<\\/p>\"],\"swift\":[\"Swift\",\" \\u7248\\u672c\\uff1a \\u60a8\\u53ef\\u4ee5\\u4f7f\\u7528 swift-algorithms 1.2.0<\\/a>\\uff0cswift-collections 1.1.4<\\/a> \\u548c swift-numerics 1.0.2<\\/a><\\/p>\\r\\n\\r\\n \\u6211\\u4eec\\u901a\\u5e38\\u4fdd\\u8bc1\\u66f4\\u65b0\\u5230 Apple\\u653e\\u51fa\\u7684\\u6700\\u65b0\\u7248Swift<\\/a>\\u3002\\u5982\\u679c\\u60a8\\u53d1\\u73b0Swift\\u4e0d\\u662f\\u6700\\u65b0\\u7248\\u7684\\uff0c\\u8bf7\\u8054\\u7cfb\\u6211\\u4eec\\uff01\\u6211\\u4eec\\u5c06\\u5c3d\\u5feb\\u66f4\\u65b0\\u3002<\\/p>\"],\"golang\":[\"Go\",\" \\u7248\\u672c\\uff1a \\u652f\\u6301 https:\\/\\/pkg.go.dev\\/github.com\\/emirpasic\\/gods@v1.18.1<\\/a> \\u548c https:\\/\\/pkg.go.dev\\/github.com\\/emirpasic\\/gods\\/v2@v2.0.0-alpha<\\/a> \\u7b2c\\u4e09\\u65b9\\u5e93\\u3002<\\/p>\"],\"python3\":[\"Python3\",\" \\u7248\\u672c\\uff1a \\u4e3a\\u4e86\\u65b9\\u4fbf\\u8d77\\u89c1\\uff0c\\u5927\\u90e8\\u5206\\u5e38\\u7528\\u5e93\\u5df2\\u7ecf\\u88ab\\u81ea\\u52a8 \\u5bfc\\u5165\\uff0c\\u5982array<\\/a>, bisect<\\/a>, collections<\\/a>\\u3002 \\u5982\\u679c\\u60a8\\u9700\\u8981\\u4f7f\\u7528\\u5176\\u4ed6\\u5e93\\u51fd\\u6570\\uff0c\\u8bf7\\u81ea\\u884c\\u5bfc\\u5165\\u3002<\\/p>\\r\\n\\r\\n \\u5982\\u9700\\u4f7f\\u7528 Map\\/TreeMap \\u6570\\u636e\\u7ed3\\u6784\\uff0c\\u60a8\\u53ef\\u4f7f\\u7528 sortedcontainers<\\/a> \\u5e93\\u3002<\\/p>\"],\"scala\":[\"Scala\",\" \\u7248\\u672c\\uff1a \\u7248\\u672c\\uff1a \\u7248\\u672c\\uff1a \\u652f\\u6301 crates.io \\u7684 rand<\\/a>\\u3001regex<\\/a> \\u548c itertools<\\/a><\\/p>\"],\"php\":[\"PHP\",\" With bcmath module.<\\/p>\"],\"typescript\":[\"TypeScript\",\" TypeScript 5.7.3<\\/p>\\r\\n\\r\\n Compile Options: --alwaysStrict --strictBindCallApply --strictFunctionTypes --target ES2024<\\/p>\\r\\n\\r\\n lodash.js<\\/a> \\u5e93\\u5df2\\u7ecf\\u9ed8\\u8ba4\\u88ab\\u5305\\u542b\\u3002<\\/p>\\r\\n\\r\\n \\u60a8\\u53ef\\u4f7f\\u7528 datastructures-js <\\/a>\\u5e93\\u6240\\u63d0\\u4f9b\\u7684\\u6570\\u636e\\u7ed3\\u6784\\u3002<\\/p>\"],\"racket\":[\"Racket\",\" Racket CS<\\/a> v8.15<\\/p>\\r\\n\\r\\n \\u4f7f\\u7528 #lang racket<\\/p>\\r\\n\\r\\n \\u5df2\\u9884\\u5148 (require data\\/gvector data\\/queue data\\/order data\\/heap). \\u82e5\\u9700\\u4f7f\\u7528\\u5176\\u5b83\\u6570\\u636e\\u7ed3\\u6784\\uff0c\\u53ef\\u81ea\\u884c require\\u3002<\\/p>\"],\"erlang\":[\"Erlang\",\"Erlang\\/OTP 26\"],\"elixir\":[\"Elixir\",\"Elixir 1.17 with Erlang\\/OTP 26\"],\"dart\":[\"Dart\",\" Dart 3.2\\u3002\\u60a8\\u53ef\\u4ee5\\u4f7f\\u7528 collection<\\/a> \\u5305<\\/p>\\r\\n\\r\\n \\u60a8\\u7684\\u4ee3\\u7801\\u5c06\\u4f1a\\u88ab\\u4e0d\\u7f16\\u8bd1\\u76f4\\u63a5\\u8fd0\\u884c<\\/p>\"],\"cangjie\":[\"Cangjie\",\" \\u7248\\u672c\\uff1a1.0.0 LTS (cjnative)<\\/p>\\r\\n\\r\\n \\u7f16\\u8bd1\\u53c2\\u6570\\uff1a \\u5feb\\u901f\\u5165\\u95e8\\u8bf7\\u67e5\\u9605\\u300c\\u4ed3\\u9889\\u7f16\\u7a0b\\u8bed\\u8a00\\u5f00\\u53d1\\u6307\\u5357\\u300d<\\/a><\\/p>\"]}",
"book": null,
"isSubscribed": false,
"isDailyQuestion": false,
"dailyRecordStatus": null,
"editorType": "CKEDITOR",
"ugcQuestionId": null,
"style": "LEETCODE",
"exampleTestcases": "3\n[[0,1],[1,2]]\n[2,8,2]\n3\n[[0,1],[0,2]]\n[1,2,4]\n4\n[[0,1],[0,2],[1,3]]\n[1,2,9,4]",
"__typename": "QuestionNode"
}
}
}clang 19<\\/code> \\u91c7\\u7528\\u6700\\u65b0 C++ 23 \\u6807\\u51c6\\uff0c\\u5e76\\u4f7f\\u7528 GCC 14 \\u63d0\\u4f9b\\u7684 libstdc++<\\/code>\\u3002<\\/p>\\r\\n\\r\\n-O2<\\/code> \\u7ea7\\u4f18\\u5316\\uff0c\\u5e76\\u63d0\\u4f9b -gline-tables-only<\\/code> \\u53c2\\u6570\\u3002AddressSanitizer<\\/a> \\u4e5f\\u88ab\\u5f00\\u542f\\u6765\\u68c0\\u6d4b out-of-bounds<\\/code> \\u548c use-after-free<\\/code> \\u9519\\u8bef\\u3002<\\/p>\\r\\n\\r\\nOpenJDK 21<\\/code>\\u3002\\u4f7f\\u7528\\u7f16\\u8bd1\\u53c2\\u6570 --enable-preview --release 21<\\/code><\\/p>\\r\\n\\r\\nPython 2.7.18<\\/code><\\/p>\\r\\n\\r\\nGCC 14<\\/code>\\uff0c\\u91c7\\u7528 GNU11 \\u6807\\u51c6\\u3002<\\/p>\\r\\n\\r\\n-O2<\\/code> \\u7ea7\\u4f18\\u5316\\uff0c\\u5e76\\u63d0\\u4f9b -g1<\\/code> \\u53c2\\u6570\\u3002 AddressSanitizer<\\/a> \\u4e5f\\u88ab\\u5f00\\u542f\\u6765\\u68c0\\u6d4b out-of-bounds<\\/code> \\u548c use-after-free<\\/code> \\u9519\\u8bef\\u3002<\\/p>\\r\\n\\r\\n\\r\\nstruct hash_entry {\\r\\n int id; \\/* we'll use this field as the key *\\/\\r\\n char name[10];\\r\\n UT_hash_handle hh; \\/* makes this structure hashable *\\/\\r\\n};\\r\\n\\r\\nstruct hash_entry *users = NULL;\\r\\n\\r\\nvoid add_user(struct hash_entry *s) {\\r\\n HASH_ADD_INT(users, id, s);\\r\\n}\\r\\n<\\/pre>\\r\\n<\\/p>\\r\\n\\r\\n\\r\\nstruct hash_entry *find_user(int user_id) {\\r\\n struct hash_entry *s;\\r\\n HASH_FIND_INT(users, &user_id, s);\\r\\n return s;\\r\\n}\\r\\n<\\/pre>\\r\\n<\\/p>\\r\\n\\r\\n\\r\\nvoid delete_user(struct hash_entry *user) {\\r\\n HASH_DEL(users, user); \\r\\n}\\r\\n<\\/pre>\\r\\n<\\/p>\"],\"csharp\":[\"C#\",\"Node.js 22.14.0<\\/code><\\/p>\\r\\n\\r\\n--harmony<\\/code> \\u6807\\u8bb0\\u6765\\u5f00\\u542f \\u65b0\\u7248ES6\\u7279\\u6027<\\/a>\\u3002<\\/p>\\r\\n\\r\\nRuby 3.2<\\/code> \\u6267\\u884c<\\/p>\\r\\n\\r\\nSwift 6.0<\\/code><\\/p>\\r\\n\\r\\nGo 1.23<\\/code><\\/p>\\r\\n\\r\\nPython 3.11<\\/code><\\/p>\\r\\n\\r\\nScala 3.3.1<\\/code><\\/p>\"],\"kotlin\":[\"Kotlin\",\"Kotlin 2.1.10<\\/code><\\/p>\"],\"rust\":[\"Rust\",\"rust 1.88.0<\\/code>\\uff0c\\u4f7f\\u7528 edition 2024\\u3002<\\/p>\\r\\n\\r\\nPHP 8.2<\\/code>.<\\/p>\\r\\n\\r\\n-O2 --disable-reflection<\\/code><\\/p>\\r\\n\\r\\n