Container With Most Water | Leetcode solution in JavaScript

— #Leetcode

problem

Given n non-negative integers a1, a2, ..., an , where each represents a point at coordinate (i, ai). n vertical lines are drawn such that the two endpoints of the line i is at (i, ai) and (i, 0). Find two lines, which, together with the x-axis forms a container, such that the container contains the most water.

Notice that you may not slant the container.

Example 1

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.

Solution using Brute Force

It might gives an error which is TLE(Time Limit Exceeded)

• Time complexity: O(n^2)
• Space complexity: O(1)
var maxArea = function (height) {
let area = 0;

for (let i = 0; i < height.length; i++) {
for (let j = i + 1; j < height.length; j++) {
let newArea = min(height[i], height[j]) * (j - i);
if (newArea > area) {
area = newArea;
}
}
}
return area;
};

var min = function (i, j) {
if (i < j) {
return i;
}
return j;
};

Solution using Two pointer

• Time complexity: O(n)
• Space complexity: O(1)
var maxArea = function (height) {
let low = 0;
let high = height.length - 1;
var area = 0;

while (low < high) {
const currArea = (height[low] > height[high] ? height[high] : height[low]) * (high - low);
area = area < currArea ? currArea : area;

if (height[low] > height[high]) {
--high;
} else {
++low;
}
}
return area;
};