package gauss;

/**
 * Implementación algoritmo del método de Gauss.
 *
 * @author Lluís Camino
 */
public class Gauss {

    public static void main(String[] args) {
        int[][] a = {
            {1, 1, -2},
            {2, -1, 4},
            {2, -1, -6}
        };
        int[] b = {9, 4, -1};
        imprimirSistema("Original", a, b);
        metodoGauss(a, b);
    }

    public static void metodoGauss(int[][] a, int[] b) {
        for (int k = 0; k < a.length - 1; k++) {
            for (int i = k + 1; i < a.length; i++) {
                int m = a[i][k] / a[k][k];
                a[i][k] = 0;
                for (int j = k + 1; j < a.length; j++) {
                    a[i][j] -= m * a[k][j];
                }
                b[i] -= m * b[k];
            }
        }

        imprimirSistema("Reducida", a, b);
    }

    public static void imprimirSistema(String texto, int[][] a, int[] b) {
        System.out.println(texto + ":");
        for (int i = 0; i < a.length; i++) {
            for (int j = 0; j < a[0].length; j++) {
                System.out.print(a[i][j] + " ");
            }
            System.out.println("| " + b[i]);
        }
        System.out.println();
    }
}