Update 2503-maximum-number-of-points-from-grid-queries.js

Author: everthis

2503-maximum-number-of-points-from-grid-queries.js

@@ -1,3 +1,115 @@
+class PQ {
+  constructor(comparator = (a, b) => a > b) {
+    this.heap = []
+    this.top = 0
+    this.comparator = comparator
+  }
+  size() {
+    return this.heap.length
+  }
+  isEmpty() {
+    return this.size() === 0
+  }
+  peek() {
+    return this.heap[this.top]
+  }
+  push(...values) {
+    values.forEach((value) => {
+      this.heap.push(value)
+      this.siftUp()
+    })
+    return this.size()
+  }
+  pop() {
+    const poppedValue = this.peek()
+    const bottom = this.size() - 1
+    if (bottom > this.top) {
+      this.swap(this.top, bottom)
+    }
+    this.heap.pop()
+    this.siftDown()
+    return poppedValue
+  }
+  replace(value) {
+    const replacedValue = this.peek()
+    this.heap[this.top] = value
+    this.siftDown()
+    return replacedValue
+  }
+
+  parent = (i) => ((i + 1) >>> 1) - 1
+  left = (i) => (i << 1) + 1
+  right = (i) => (i + 1) << 1
+  greater = (i, j) => this.comparator(this.heap[i], this.heap[j])
+  swap = (i, j) => ([this.heap[i], this.heap[j]] = [this.heap[j], this.heap[i]])
+  siftUp = () => {
+    let node = this.size() - 1
+    while (node > this.top && this.greater(node, this.parent(node))) {
+      this.swap(node, this.parent(node))
+      node = this.parent(node)
+    }
+  }
+  siftDown = () => {
+    let node = this.top
+    while (
+      (this.left(node) < this.size() && this.greater(this.left(node), node)) ||
+      (this.right(node) < this.size() && this.greater(this.right(node), node))
+    ) {
+      let maxChild =
+        this.right(node) < this.size() &&
+        this.greater(this.right(node), this.left(node))
+          ? this.right(node)
+          : this.left(node)
+      this.swap(node, maxChild)
+      node = maxChild
+    }
+  }
+}
+
+/**
+ * @param {number[][]} grid
+ * @param {number[]} queries
+ * @return {number[]}
+ */
+const maxPoints = function (grid, queries) {
+  const m = grid.length, n = grid[0].length, k = queries.length
+  const q = [...queries]
+  const pq = new PQ((a, b) => a[1] < b[1])
+  const dirs = [[0, 1],[0, -1],[1, 0],[-1,0]]
+  
+  q.sort((a, b) => a - b)
+  const hash = {}
+  const visited = Array.from({ length: m }, () => Array(n).fill(false))
+
+  pq.push([[0, 0], grid[0][0]])
+  visited[0][0] = true
+
+  let cnt = 0
+  for(const e of q) {
+    while(!pq.isEmpty()) {
+      const [coord, v] = pq.peek()
+      const [r, c] = coord
+      if(e <= v) break
+      pq.pop()
+      for(const [dr, dc] of dirs) {
+        const nr = r + dr, nc = c + dc
+        if(nr >= 0 && nr < m && nc >= 0 && nc < n && visited[nr][nc] === false) {
+          visited[nr][nc] = true
+          pq.push([[nr, nc], grid[nr][nc]])
+        }
+      }
+      cnt++
+    }
+
+    hash[e] = cnt
+  }
+// console.log(hash)
+  return queries.map(e => hash[e])
+}
+
+// another
+
+
 /**
  * @param {number[][]} grid
  * @param {number[]} queries