package ru.sql.java.luffi;

public class CppToJava {
    private static final int n = 7;

    public static void main(String[] args) {
        double[] a = {0, 1, 2, 3, 2, 1, 1}, b = {2, 3, 5, 7, 5, 3, 2}, c = {1, 1, 2, 3, 2, 1, 0}, d = {4, 10, 27, 46, 27, 10, 4};

        print_array(a, n, "a");
        print_array(b, n, "b");
        print_array(c, n, "c");
        print_array(d, n, "d");

        printf("PROVERKA DIAGONAL'NUX ELEMENTOV: ");
        int k = 0;
        for (int i = 0; i <= n - 1; i++) {
            if (fabs(b[i]) < (fabs(a[i]) + fabs(c[i])))
                k++;
        }

        if (k == 0) {
            printf(" VUPOLNENO \n");
        } else {
            printf(" NE VIPOLNENO!!!!\n");
        }

        double[] A = new double[n], B = new double[n];

        A[0] = -c[0] / b[0];
        B[0] = d[0] / b[0];
        printf("\nA[1]=%1.3f  ", A[0]);
        printf("\nB[1]=%1.3f\n  ", B[0]);

        for (int i = 1; i < n - 1; i++) {
            double e = a[i] * A[i - 1] + b[i];
            A[i] = -c[i] / e;
            B[i] = (d[i] - a[i] * B[i - 1]) / e;
            printf("\nA[%d]=%1.3f  ", i + 1, A[i]);
            printf("\nB[%d]=%1.3f\n  ", i + 1, B[i]);
        }

        double[] x = new double[n];
        x[n - 1] = (d[n - 1] - a[n - 1] * B[n - 2]) / (b[n - 1] + a[n - 1] * A[n - 2]);
        for (int i = n - 2; i >= 0; i--) {
            x[i] = x[i + 1] * A[i] + B[i];
        }

        printf("\n\n REWENIE SISTEMU:\n\n");

        for (int i = 0; i <= n - 1; i++) {
            printf("x[%d]=%2.2f  ", i + 1, x[i]);
        }
    }

    private static void print_array(double[] array, int count, String arrayName) {
        for (int i = 0; i <= n - 1; i++) {
            printf("%s[%d]=%2.2f  ", arrayName, i + 1, array[i]);
        }
        printf("\n\n");
    }

    private static double fabs(double value) {
        return Math.abs(value);
    }

    private static void printf(String format, Object... args) {
        System.out.printf(format, args);
    }
}