Physics mechanics question doubt??!!?

A wedge of mass 'M' and angle of inclination θ, is arranged in such a manner that one end of a spring of force constant 'k' is attached to it (the other end is fixed to a wall), and a block of mass 'm' is sliding down it tied to a massless string (with one end of the string fixed to the same wall), find the compression of the spring under equilibrium condition.