import java.util.Scanner;

public class Vectors3D
{
	public static void main(String[] args)
	{
		double[] u= new double[3];
		double[] v= new double[3];
		char[] axes={'X', 'Y', 'Z'};
		
		Scanner scan= new Scanner(System.in);
		
		for(int i=0; i < u.length; i++) {
			System.out.print("Enter " + axes[i] + "-component of vector u: ");
			u[i]=scan.nextDouble();	
		}

		System.out.println();
		for(int i=0; i < v.length; i++) {
			System.out.print("Enter " + axes[i] + "-component of vector v: ");
			v[i]=scan.nextDouble();	
		}

		double norm_u  = 0.0;
		double norm_v  = 0.0;
		double u_dot_v = 0.0;
		
		for(int i=0; i < 3; i++) {
			norm_u  += u[i]*u[i];
			norm_v  += v[i]*v[i];
			u_dot_v += u[i]*v[i];
		}
					
		norm_u = Math.sqrt(norm_u);
		norm_v = Math.sqrt(norm_v);
		
		double theta = Math.acos( u_dot_v/(norm_u * norm_v));
		
		System.out.println();
		System.out.println("1) Norm of u = " + norm_u);
		System.out.println("2) Norm of v = " + norm_v);
		System.out.println("3) u dot v   = " + u_dot_v);
		System.out.println("4) Theta     = " + theta*180.0/Math.PI);
	}
}