14. If the directrix of the parabola $y ^ { 2 } = 2 p x ( p > 0 )$ passes through a focus of the hyperbola $x ^ { 2 } - y ^ { 2 } = 1$, then $p = $ $\_\_\_\_$
14. If the directrix of the parabola $y ^ { 2 } = 2 p x ( p > 0 )$ passes through a focus of the hyperbola $x ^ { 2 } - y ^ { 2 } = 1$, then $p = $ $\_\_\_\_$