generate-random-point-in-a-circle.md

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

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]]

Solution

class Solution {
public:
    double radius, x_center, y_center;
    Solution(double _radius, double _x_center, double _y_center) {
        radius = _radius;
        x_center = _x_center;
        y_center = _y_center;
    }
    
    vector<double> randPoint() {
        double theta = ((double) rand()/RAND_MAX)*2*M_PI;
        double r = sqrt((double) rand()/RAND_MAX) * radius;
        double x = r * cos(theta) + x_center;
        double y = r * sin(theta) + y_center;
        return {x, y};
    }
};

Accepted