Added geometry

content/geometry/angle.cpp

@@ -0,0 +1,8 @@
+/**
+ * Author: me
+ * Description: rad - deg converter.
+ * Time: $O(1)$
+ */
+
+long double deg_to_rad(long double d) {return d*M_PI/180.0;}
+long double rad_to_deg(long double r) {return r*180.0/M_PI;}

content/geometry/chapter.tex

@@ -0,0 +1,4 @@
+\chapter{Geometry}
+
+\kactlimport{angle.cpp}
+\kactlimport{point.cpp}

content/geometry/point.cpp

@@ -0,0 +1,54 @@
+/**
+ * Author: me
+ * Description: Point and Vector.
+ * Time: N/A
+ */
+
+#define Vector Point /** keep-include */
+
+template<class T>
+struct Point {
+	// CAREFUL
+	static constexpr T eps = 1e-9;
+
+	T x, y;
+	Point() {}
+	Point(T _x, T _y) {x = _x; y = _y;}
+
+	// Comparison
+	bool operator<(Point p) const {
+		if (abs(x - p.x) > eps) return x < p.x;
+		return y < p.y;
+	}
+
+	bool operator==(Point p) const {
+		return (abs(x-p.x) < eps) && (abs(y-p.y) < eps);
+	}
+
+	// Calculation
+	T operator&(Vector v) const {return x*v.y - y*v.x;}
+	T operator*(Vector v) const {return x*v.x + y*v.y;}
+	Vector operator*(T d) const {return Vector(x*d, y*d);}
+	Vector operator/(T d) const {return Vector(x/d, y/d);}
+	Vector operator+(Vector v) const {return Vector(x+v.x,y+v.y);}
+	Vector operator-(Vector v) const {return Vector(x-v.x,y-v.y);}
+
+	void operator*=(T d) {x *= d; y *= d;}
+	void operator/=(T d) {x /= d; y /= d;}
+	void operator+=(Vector v) {x += v.x; y += v.y;}
+	void operator-=(Vector v) {x -= v.x; y -= v.y;}
+
+	T len2() {return x*x + y*y;}
+	long double len() {return sqrt((long double)(len2()));}
+	T dist2(Point p) {return (x-p.x)*(x-p.x) + (y-p.y)*(y-p.y);}
+	long double dist(Point p) {return sqrt(dist2(p));}
+
+	// Rotate to the left
+	Point rotated(long double a)
+	{return Point(x*cos(a)-y*sin(a),x*sin(a)+y*cos(a));}
+	void rotate(long double a) {
+		T cx = x*cos(a) - y*sin(a);
+		T cy = x*sin(a) + y*cos(a);
+		x = cx; y = cy;
+	}
+};

content/kactl.tex

@@ -24,5 +24,6 @@
 	\kactlchapter{data-structures}
 	\kactlchapter{graph}
 	\kactlchapter{number-theory}
+	\kactlchapter{geometry}
 	\end{multicols*}
 \end{document}

content/number-theory/chapter.tex

@@ -1,2 +1,2 @@
-\chapter{number-theory}
+\chapter{Number Theory}
 \kactlimport{modInverse.cpp}