const std = @import("std");
const math = std.math;

const Rect = struct {
    const Self = @This();
    width: f64,
    height: f64,

    fn area(self: Self) f64 {
        return self.width * self.height;
    }

    fn perim(self: Self) f64 {
        return 2 * self.width + 2 * self.height;
    }
};

const Circle = struct {
    const Self = @This();
    radius: f64,

    fn area(self: Self) f64 {
        return math.pi * self.radius * self.radius;
    }

    fn perim(self: Self) f64 {
        return 2 * math.pi * self.radius;
    }
};

fn measure(comptime T: type, geometry: T) void {
    std.debug.print("{}\n{}\n{}\n", .{
        geometry,
        geometry.area(),
        geometry.perim(),
    });
}

pub fn main() anyerror!void {
    var r = Rect{ .width = 3, .height = 4 };
    var c = Circle{ .radius = 5 };

    measure(Rect, r);
    measure(Circle, c);
}