How could I get the histogram corresponding to probability of finding the predator-prey model in specific integer combinations please?

I have the following system :

dy0/dt = a*y0 - b*y0*y1

dy1/dt = -c * y1 + e *y0*y1

y0 =12

y1 = 5

a=15

b=2

c=5

e=0.5