public int getMetric(State state) {
        int sum = 0;
        for (int x = 0; x < this.rows; x++) {
            for (int y = 0; y < this.columns; y++) {
                Point point = findCoordinate(state, this.array[x][y]);
                sum = (x-point.x) + (y- point.y);
            }
        }
        return sum;
    }

    private Point findCoordinate(State state, int value) {
        for (int i = 0; i < this.rows; i++) {
            for (int j = 0; j < columns; j++) {
                if (value == state.array[i][j]) {
                    return new Point(i, j);
                }
            }
        }
        throw new NullPointerException("Coordinate not found");
    }