Write a C$++$ program that use struct to represent $3$D point coordinate $(x,y,z.$ It asks user for two $3$D point coordinates and output the midpoint of the two points.

a$.$ In main$(),$ get the input values from the user and store them in two struct variables for two $3$D points P$1(x_1,y_1,z_1)$ and P$2(x_2,y_2,z_2)$

b$.$ Create a function to calculate the midpoint $(\frac{x_1+x_2}{2},\frac{y_1+y_2}{2},\frac{z_1+z_2}{2}).$ This function takes two struct variables $(3$D points P$1$ and P$2)$ as input parameters and returns a struct variable for midpoint.

c$.$ In main$(),$ call the user$-$defined function to get the midpoint and output the coordinate of the midpoint