You can’t print the two values by using x[i]. You must print them one-by-one.
You probably want something like:
for (i=0;i<12;i++)
{
    printf("\t index %d value %f, %f  \n\r",i, x[i].a, x[i].b);
}
1
solved Printing Array in struct
 
You can’t print the two values by using x[i]. You must print them one-by-one.
You probably want something like:
for (i=0;i<12;i++)
{
    printf("\t index %d value %f, %f  \n\r",i, x[i].a, x[i].b);
}
1
solved Printing Array in struct