478. Generate Random Point in a Circle LeetCode Solution

In this guide, you will get 478. Generate Random Point in a Circle LeetCode Solution with the best time and space complexity. The solution to Generate Random Point in a Circle problem is provided in various programming languages like C++, Java, and Python. This will be helpful for you if you are preparing for placements, hackathons, interviews, or practice purposes. The solutions provided here are very easy to follow and include detailed explanations.

Problem Statement
Complexity Analysis
Generate Random Point in a Circle solution in C++
Generate Random Point in a Circle solution in Java
Generate Random Point in a Circle solution in Python
Additional Resources

478. Generate Random Point in a Circle LeetCode Solution image

Problem Statement of Generate Random Point in a Circle

Given the radius and the position of the center of a circle, implement the function randPoint which generates a uniform random point inside the circle.
Implement the Solution class:

Solution(double radius, double x_center, double y_center) initializes the object with the radius of the circle radius and the position of the center (x_center, y_center).
randPoint() returns a random point inside the circle. A point on the circumference of the circle is considered to be in the circle. The answer is returned as an array [x, y].

Example 1:

Input
[“Solution”, “randPoint”, “randPoint”, “randPoint”]
[[1.0, 0.0, 0.0], [], [], []]
Output
[null, [-0.02493, -0.38077], [0.82314, 0.38945], [0.36572, 0.17248]]

Explanation
Solution solution = new Solution(1.0, 0.0, 0.0);
solution.randPoint(); // return [-0.02493, -0.38077]
solution.randPoint(); // return [0.82314, 0.38945]
solution.randPoint(); // return [0.36572, 0.17248]

Constraints:

0 < radius <= 108
-107 <= x_center, y_center <= 107
At most 3 * 104 calls will be made to randPoint.

Complexity Analysis

Time Complexity:
Space Complexity:

478. Generate Random Point in a Circle LeetCode Solution in C++

class Solution {
 public:
  Solution(double radius, double x_center, double y_center)
      : radius(radius), x_center(x_center), y_center(y_center) {}

  vector<double> randPoint() {
    const double length = sqrt(distribution(generator)) * radius;
    const double degree = distribution(generator) * 2 * M_PI;
    const double x = x_center + length * cos(degree);
    const double y = y_center + length * sin(degree);
    return {x, y};
  }

 private:
  const double radius;
  const double x_center;
  const double y_center;
  default_random_engine generator;
  uniform_real_distribution<double> distribution =
      uniform_real_distribution<double>(0.0, 1.0);
};
/* code provided by PROGIEZ */

478. Generate Random Point in a Circle LeetCode Solution in Java

class Solution {
  public Solution(double radius, double x_center, double y_center) {
    this.radius = radius;
    this.x_center = x_center;
    this.y_center = y_center;
  }

  public double[] randPoint() {
    final double length = Math.sqrt(Math.random()) * radius;
    final double degree = Math.random() * 2 * Math.PI;
    final double x = x_center + length * Math.cos(degree);
    final double y = y_center + length * Math.sin(degree);
    return new double[] {x, y};
  }

  private double radius;
  private double x_center;
  private double y_center;
}
// code provided by PROGIEZ

478. Generate Random Point in a Circle LeetCode Solution in Python

class Solution:
  def __init__(self, radius: float, x_center: float, y_center: float):
    self.radius = radius
    self.x_center = x_center
    self.y_center = y_center

  def randPoint(self) -> list[float]:
    length = math.sqrt(random.uniform(0, 1)) * self.radius
    degree = random.uniform(0, 1) * 2 * math.pi
    x = self.x_center + length * math.cos(degree)
    y = self.y_center + length * math.sin(degree)
    return [x, y]
 # code by PROGIEZ