todo:1172.餐盘栈

src/leecode/javascript/1172.餐盘栈.js

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+/*
+ * @lc app=leetcode.cn id=1172 lang=javascript
+ *
+ * [1172] 餐盘栈
+ */
+
+// @lc code=start
+/**
+ * @param {number} capacity
+ */
+var DinnerPlates = function (capacity) {
+  this.capacity = capacity;
+  this.table = [];
+  this.pushStack = [];
+  this.popStack = [];
+};
+
+/**
+ * @param {number} val
+ * @return {void}
+ */
+DinnerPlates.prototype.push = function (val) {
+  // const stack = this.table.find(cur => cur.length < this.capacity);
+  // 写入栈为空，说明要新建一个栈
+  if (this.pushStack.length === 0) {
+    this.table.push([val]);
+    this.pushStack.push(this.table.length - 1);
+    this.popStack.push(this.table.length - 1);
+  } else {
+    //直接推入当前写入栈，这里不会改变弹出栈的索引
+    const pushIndex = this.pushStack[this.pushStack.length - 1];
+    this.table[pushIndex].push(val);
+    if (this.table[pushIndex].length === this.capacity) 
+      this.pushStack.pop();
+    }
+};
+
+/**
+ * @return {number}
+ */
+DinnerPlates.prototype.pop = function () {
+  if (this.popStack.length === 0) return -1;
+  const popIndex = this.popStack[this.popStack.length - 1];
+  const cur = this.table[popIndex];
+  const ret = cur.pop();
+  if (cur.length === 0) {
+    //栈空,pop导致的栈空要移除该栈
+    this.table.splice(index, 1);
+    this.popStack.pop();
+  } else {
+    //有栈可写入，将该栈索引写入push栈
+    if (this.pushStack.find(cur => cur === popIndex) === undefined) {
+      //插入该索引的位置
+      const insertIndex = this.pushStack.findIndex(cur => cur < popIndex);
+      if (insertIndex === -1) {
+        this.pushStack.push(popIndex);
+      } else {
+        this.pushStack = [this.pushStack.slice(0, insertIndex), popIndex, this.pushStack.slice(insertIndex + 2)];
+      }
+    }
+  }
+  return ret;
+};
+
+/**
+ * @param {number} index
+ * @return {number}
+ */
+DinnerPlates.prototype.popAtStack = function (index) {
+  const arr = this.table[index];
+  if (arr?.length) {
+    return arr.pop();
+  } else {
+    return -1;
+  }
+};
+
+const D = new DinnerPlates(2); // 初始化，栈最大容量 capacity = 2
+
+for (let i = 0; i < 2523268; i++) {
+  console.log(D.push(i));
+}
+
+
+
+const a = [1, 2, 3];
+console.log(a.findIndex(cur => cur > 3));
+