\[\boxed{\mathbf{151}.}\]
\[1)\ y = |x^{2} - 1|\]
\[2)\ y = |4 - x^{2}|\]
\[3)\ y = |(x - 1)(x + 3)|\]
\[4)\ y = |x(x - 2)|\]
\[5)\ y = x^{2} - 2|x| - 3\]
\[6)\ y = x^{2} + |x| - 2\]