Create 2973-find-number-of-coins-to-place-in-tree-nodes.js

Author: everthis

2973-find-number-of-coins-to-place-in-tree-nodes.js

@@ -0,0 +1,133 @@
+/**
+ * @param {number[][]} edges
+ * @param {number[]} cost
+ * @return {number[]}
+ */
+var placedCoins = function (edges, cost) {
+  let tree = buildRootedTree(buildGraph(cost.length, edges), 0)
+  let res = Array(cost.length).fill()
+
+  function solve(root) {
+    let node = tree[root]
+    let c = cost[root]
+
+    if (c > 0) node.max1 = c
+    else node.min1 = c
+
+    for (let child of node.aNodes) {
+      solve(child)
+      let childNode = tree[child]
+      opt(node, childNode.max1)
+      opt(node, childNode.max2)
+      opt(node, childNode.max3)
+      opt(node, childNode.min1)
+      opt(node, childNode.min2)
+      opt(node, childNode.min3)
+    }
+
+    let cnt =
+      !!node.min1 +
+      !!node.min2 +
+      !!node.min3 +
+      !!node.max1 +
+      !!node.max2 +
+      !!node.max3
+    if (cnt < 3) {
+      res[root] = 1
+      return
+    }
+
+    res[root] = 0
+    let v = node.max1 * node.max2 * node.max3
+    if (v > res[root]) res[root] = v
+    v = node.max1 * node.min1 * node.min2
+    if (v > res[root]) res[root] = v
+  }
+
+  solve(0)
+  return res
+}
+
+/**
+ * @typedef {{ aNodes: number[] }} TGraphNode
+ * @param {number} n
+ * @param {[number,number,number?][]} edges
+ * @return {TGraphNode[]}
+ */
+function buildGraph(n, edges) {
+  /** @type {TGraphNode[]} */
+  let nodes = []
+  for (let i = 0; i < n; i++) nodes.push({ aNodes: [] })
+
+  let m = edges.length
+  for (let i = 0; i < m; i++) {
+    let [u, v] = edges[i]
+    nodes[u].aNodes.push(v)
+    nodes[v].aNodes.push(u)
+  }
+
+  return nodes
+}
+
+/**
+ * @typedef {{ parent: number, min1, min2, min3, max1, max2, max3 }} TTreeNode
+ * @param {(TGraphNode & TTreeNode)[]} graph
+ * @param {number} root
+ * @param {number?} parent
+ * @return {(TGraphNode & TTreeNode)[]}
+ */
+function buildRootedTree(graph, root, parent) {
+  let node = graph[root]
+  node.parent = parent
+
+  let m = node.aNodes.length
+  let parentIndex = undefined
+  for (let i = 0; i < m; i++) {
+    if (node.aNodes[i] == parent) parentIndex = i
+    else buildRootedTree(graph, node.aNodes[i], root)
+  }
+
+  if (parentIndex != undefined) {
+    node.aNodes[parentIndex] = node.aNodes[m - 1]
+    node.aNodes.pop()
+  }
+
+  node.max1 = 0
+  node.max2 = 0
+  node.max3 = 0
+  node.min1 = 0
+  node.min2 = 0
+  node.min3 = 0
+  return graph
+}
+
+/**
+ * @param {TTreeNode} node
+ * @param {number} cost
+ */
+function opt(node, cost) {
+  if (!cost) return
+  if (cost > 0) {
+    if (cost >= node.max1) {
+      node.max3 = node.max2
+      node.max2 = node.max1
+      node.max1 = cost
+    } else if (cost >= node.max2) {
+      node.max3 = node.max2
+      node.max2 = cost
+    } else if (cost > node.max3) {
+      node.max3 = cost
+    }
+  } else {
+    if (cost <= node.min1) {
+      node.min3 = node.min2
+      node.min2 = node.min1
+      node.min1 = cost
+    } else if (cost <= node.min2) {
+      node.min3 = node.min2
+      node.min2 = cost
+    } else if (cost < node.min3) {
+      node.min3 = cost
+    }
+  }
+}