03.Triangle

package TestJan;

import java.text.DecimalFormat;
        import java.util.Scanner;

public class Triangle {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);

        DecimalFormat decimalFormat = new DecimalFormat("0.#");

        double a = Double.parseDouble(scanner.nextLine());
        double b = Double.parseDouble(scanner.nextLine());
        double c = Double.parseDouble(scanner.nextLine());

        boolean checkIsTriangle = !((a < b + c) && (b < a + c) && (c < a + b));
        boolean checkIsScalene = (a != b && b != c && a != c);
        boolean checkIsIsosceles = ((a == b || b == c || a == c) && (a != b || b != c || a != c));
        boolean checkIsEquilateral = (a == b && b == c && a == c);

        if (checkIsTriangle) {
            System.out.println("There is no triangle with sides " + decimalFormat.format(a) + ", " + decimalFormat.format(b) + " and " + decimalFormat.format(c)+".");
        } else if (checkIsScalene) {
            System.out.println("Triangle with sides " + decimalFormat.format(a) + ", " + decimalFormat.format(b) + " and " + decimalFormat.format(c) + " is scalene.");
        } else if (checkIsIsosceles) {
            System.out.println("Triangle with sides " + decimalFormat.format(a) + ", " + decimalFormat.format(b) + " and " + decimalFormat.format(c) + " is isosceles.");

        } else if (checkIsEquilateral) {
            System.out.println("Triangle with sides " + decimalFormat.format(a) + ", " + decimalFormat.format(b) + " and " + decimalFormat.format(c) + " is equilateral.");

        }
    }
}