package maman11;

import java.util.Scanner;

public class Triangle
{
    public static void main(String[] args)
    {
        Scanner scan = new Scanner(System.in);
        System.out.println("This program calculates the area and the perimeter of given triangle.");
        System.out.println("Please enter thr three lengths of the triangle's sides");

        int a = scan.nextInt();
        int b = scan.nextInt();
        int c = scan.nextInt();

        int perimeter = a + b + c;
        double s = perimeter / 2.0;
        double sqrtExpression = s * (s - a) * (s - b) * (s - c);
        String errorValues = "";

        if (a <= 0)
            errorValues += "\na: " + a;
        if (b <= 0)
            errorValues += "\nb: " + b;
        if (c <= 0)
            errorValues += "\nc: " + c;

        if (!errorValues.equals(""))
        {
            System.out.println("The triangle's edges can't be negative");
            System.out.println("The invalid enges are: " + errorValues);
        }
        else
        {
            if (a + b < c)
                errorValues += "\na: " + a + "\nb: " + b + "\n" + a + " + " + b + " >=! " + c;
            else if (a + c < b)
                errorValues += "\na: " + a + "\nc: " + c + "\n" + a + " + " + c + " >=! " + b;
            else if (b + c < a)
                errorValues += "\nb: " + b + "\nc: " + c + "\n" + b + " + " + c + " >=! " + a;

            if (!errorValues.equals(""))
            {
                System.out.println("The triangle inequality isn't fulfill");
                System.out.println("The invalid enges are: " + errorValues);
            }
            else
            {
                System.out.println("perimeter: " + perimeter);
                System.out.println("area: " + Math.sqrt(sqrtExpression));
            }
        }
    }
}