111

import java.io.IOException;
import java.io.RandomAccessFile;
import java.util.Locale;

public class Main {

    private static void printResult(double tau_1, double tau_2, double x_2, int param, RandomAccessFile common) throws IOException {
        double temp;
        if (tau_1 > 0) {
            temp = (x_2 * (param * tau_1 + 1) + 5 * param * tau_1) / 10;
            if (temp > 0 && temp < 1) {
                common.writeInt(param);
                common.seek(2);
                common.writeChars(String.format(Locale.US, "%.4f", temp));
                common.seek(9);
                common.writeChars(String.format(Locale.US, "%.1f", x_2));
                common.seek(14);
                common.writeChars(String.format(Locale.US, "%.4f", tau_1));
                common.seek(23);
                common.writeChars(String.format(Locale.US, "%.4f", tau_1));
                common.seek(33);
                common.writeChars(String.format(Locale.US, "%.4f", tau_1 * param));
                common.seek(43);
                common.writeChars("\n");
            }
        }
        if (tau_2 > 0) {
            temp = (x_2 * (param * tau_2 + 1) + 5 * param * tau_2) / 10;
            if (temp > 0 && temp < 1) {
                common.writeInt(param);
                common.seek(2);
                common.writeChars(String.format(Locale.US, "%.4f", temp));
                common.seek(9);
                common.writeChars(String.format(Locale.US, "%.1f", x_2));
                common.seek(14);
                common.writeChars(String.format(Locale.US, "%.4f", tau_2));
                common.seek(23);
                common.writeChars(String.format(Locale.US, "%.4f", tau_2));
                common.seek(33);
                common.writeChars(String.format(Locale.US, "%.4f", tau_2 * param));
                common.seek(43);
                common.writeChars("\n");
            }
        }
    }

    public static void main(String[] args) throws IOException {
        RandomAccessFile common = new RandomAccessFile("common.txt", "rw");
        common.writeChars("A  X1     X2   TAU      P2        P5       \n");
        int[] param = {1, 2, 4};
        double a, b, c, x_2, tau_1, tau_2;
        for (int i = 0; i < 3; i++)
            for (int j = 0; j < 151; j++) {
                x_2 = -5.0 + j * 0.1;
                a = param[i] * (x_2 + 5) * Math.pow(Math.E, (x_2 / (1 + x_2 / 20))) / -10;
                b = param[i] * (x_2 + 5) / -10 + Math.pow(Math.E, (x_2 / (1 + x_2 / 20))) + x_2 * Math.pow(Math.E, (x_2 / (1 + x_2 / 20))) / -10;
                c = x_2 / -10;
                if (Math.pow(b, 2) - 4 * a * c <= 0)
                    System.out.println("Корни отсутствуют при a= " + param[i] + ", x_2= " + String.format(Locale.US, "%.1f", x_2));
                else if (Math.pow(b, 2) - 4 * a * c > 0) {
                    tau_1 = (-b + Math.sqrt(Math.pow(b, 2) - 4 * a * c)) / (2 * a);
                    tau_2 = (-b - Math.sqrt(Math.pow(b, 2) - 4 * a * c)) / (2 * a);
                    System.out.println("Корни квадратного уравнения при a= " + param[i] + ", x_2= "
                            + String.format(Locale.US, "%.1f", x_2) + ". tau_1 = " + String.format(Locale.US, "%.4f", tau_1) + " tau_2 = " + String.format(Locale.US, "%.4f", tau_2));
                    printResult(tau_1, tau_2, x_2, param[i], common);
                }
            }
        common.close();
    }
}