Add: Exercise 11. Container With Most Water

Author: BlackBeast593

11-container-with-most-water/README.md

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+# 11. Container With Most Water
+You are given an integer array `height` of length `n`. There are `n` vertical lines drawn such that
+the two endpoints of the ith line are `(i, 0)` and `(i, height[i])`.
+
+Find two lines that together with the x-axis form a container, such that the container contains the
+most water.
+
+Return the maximum amount of water a container can store.
+
+Notice that you may not slant the container.
+
+## Examples
+
+### Example 1:
+![Example 1](./img1.jpg)
+
+**Input:** `height` = [1,8,6,2,5,4,8,3,7]
+
+**Output:** 49
+
+**Explanation:** The above vertical lines are represented by array `[1,8,6,2,5,4,8,3,7]`. In this
+case, the max area of water (blue section) the container can contain is 49.
+
+### Example 2:
+**Input:** `height` = [1,1]
+
+**Output:** 1
+
+## Constraints
+- `n == height.length`
+- `2 <= n <= 10^5`
+- `0 <= height[i] <= 10^4`

11-container-with-most-water/img1.jpg

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+/**
+ * Determines the maximum water volume between pairs of lines in `height`.
+ * Implements a two-pointer approach, moving from the edges to the center.
+ * The water volume is calculated as the min height of the two lines times the width.
+ * @param {number[]} height - Heights of the lines.
+ * @return {number} - Maximum water volume that can be contained.
+ */
+var maxArea = function(height) {
+    const n = height.length
+
+    // We initialize the container limits with two pointers
+    let left = 0 // Index of the left limit (pointer) of the container
+    let right = n - 1 // Index of the right limit of the container
+    let maxArea = 0
+
+    while (left < right) {
+        const base = right - left
+        const area = Math.min(height[left], height[right]) * base
+
+        maxArea = Math.max(area, maxArea)
+
+        // This is the most critical part, which pointer to move?
+        // The smaller height limits the max area of the container, so we shift the
+        // pointer with the smaller height to the left or right, searching for a bigger
+        // height
+        if (height[left] < height[right]) {
+            left++
+        } else {
+            right--
+        }
+    }
+
+    return maxArea
+};
+
+module.exports = maxArea

11-container-with-most-water/index.js

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+{
+  "name": "11-container-with-most-water",
+  "version": "1.0.0",
+  "description": "You are given an integer array `height` of length `n`. There are `n` vertical lines drawn such that the two endpoints of the ith line are `(i, 0)` and `(i, height[i])`.",
+  "main": "index.js",
+  "scripts": {
+    "start": "node index.js",
+    "debug": "node --inspect-brk index.js",
+    "test": "node test.js"
+  },
+  "keywords": [],
+  "author": "",
+  "license": "ISC"
+}

11-container-with-most-water/package.json

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+const assert = require('assert')
+const maxArea = require('./index')
+
+const tt = [
+    {
+        height: [1,8,6,2,5,4,8,3,7],
+        expected: 49
+    },
+    {
+        height: [1,1],
+        expected: 1
+    },
+]
+
+for (const t of tt) {
+    assert.strict.deepEqual(maxArea(t.height), t.expected)
+}