How do I map an array of pointers using array notation

Runtimes OpenMP
3

I am getting:
$ cat t1.cpp#include
int main() {
int *a[1024];

#pragma omp target enter data map(alloc: a[0:1024])
for (int i=0;i<1024;i++)
#pragma omp target enter data map(to: a[i][0:1])

#pragma omp target map(alloc: a)
{

}

}
t1.cpp:8:27: error: ‘#pragma omp target enter data’ cannot be an immediate substatement
#pragma omp target enter data map(to: a[i][0:1])
^
1 error generated.