• # For Solution

You are given a stream of points on the X-Y plane. Design an algorithm that:

• Adds new points from the stream into a data structure. Duplicate points are allowed and should be treated as different points.
• Given a query point, counts the number of ways to choose three points from the data structure such that the three points and the query point form an axis-aligned square with positive area. Detect Squares solution leetcode

An axis-aligned square is a square whose edges are all the same length and are either parallel or perpendicular to the x-axis and y-axis.

Implement the `DetectSquares` class: Detect Squares solution leetcode

• `DetectSquares()` Initializes the object with an empty data structure.
• `void add(int[] point)` Adds a new point `point = [x, y]` to the data structure.
• `int count(int[] point)` Counts the number of ways to form axis-aligned squares with point `point = [x, y]` as described above.

Detect Squares solution leetcode

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```Input
[[], [[3, 10]], [[11, 2]], [[3, 2]], [[11, 10]], [[14, 8]], [[11, 2]], [[11, 10]]]
Output
[null, null, null, null, 1, 0, null, 2]

Explanation
DetectSquares detectSquares = new DetectSquares();
detectSquares.count([11, 10]); // return 1. You can choose:
//   - The first, second, and third points
detectSquares.count([14, 8]);  // return 0. The query point cannot form a square with any points in the data structure.
detectSquares.add([11, 2]);    // Adding duplicate points is allowed.
detectSquares.count([11, 10]); // return 2. You can choose:
//   - The first, second, and third points
//   - The first, third, and fourth points
```

Detect Squares solution leetcode

• `point.length == 2`
• `0 <= x, y <= 1000`
• At most `5000` calls in total will be made to `add` and `count`.