Cosines

import java.util.*;
import java.lang.*;
public class Cosines
{
    public static void main(){
        System.out.println("This program finds the value of the third side of a triangle using two sides and an angle.\n"); 
        System.out.println("Enter side 1 (a) :");
        Scanner input = new Scanner(System.in);
        double a = input.nextDouble();
        System.out.println("Enter side 2 (b) :");
        double b = input.nextDouble();
        System.out.println("Enter the angle where the two sides intersect (C) :");
        double C = input.nextDouble();
        input.close();
        if (C >= 180){
        System.out.println("Invalid input");
        System.exit(0);
        }
        double cSquared = (a*a)+(b*b)-((2*a*b)*(Math.cos(C)));
        double c = Math.sqrt(cSquared);
        System.out.println("The value of c is: " + c);
    }
}