t0 = X3-Z3 t1 = X2+Z2 t2 = X3+Z3 t3 = X2-Z2 t4 = t2*t3 t5 = t0*t1 t6 = t5+t4 t7 = t6^2 X5 = Z1*t7 t8 = X3-Z3 t9 = X2+Z2 t10 = X3+Z3 t11 = X2-Z2 t12 = t10*t11 t13 = t8*t9 t14 = t13-t12 t15 = t14^2 Z5 = X1*t15