OpenCL kernel and odd copy

I’m studying OpenCL and I’m trying to do this exercise but I don’t know how to write the corresponding kernel code in order to avoid the branch-divergence problem.

I write something like that but I don’t know if I’ll problem or branch divergence

__kernel void oddcopy(const __global const int *a, __global int*b) {
    int gid = get_global_id(0);
    b[gid] = a[gid];

I hope my question is clear because I’m not very well at English, sorry.

Thanks in advance for the help, if there are problems let me know!