function - Passing an element of an array of structs in C -

i trying pass 1 of 20 "database" structs made

here prototype function "add"

void add(struct database test); 

i want pass database struct , i'll call "test"

here database structure

struct database {     char id[6];     char duration[3]; };  main() {     char menu;    struct database employee[20]; // make 20 employee variables    int = 0;                    /*a counter use edit structs                                     ie a=2  "employee[a]" = "employee[2]" */ 

i call function this:

add(employee[a]); a++;  /*once exits want go next employee        variable increment counter */ 

the actual function looks this:

void add(struct database test) {     static int = 0;      printf("\nplease enter 5 digit employee number: ");     scanf("%s", test[a].id);      a++ } 

while doing error:

error e2094 assignment.c 64: 'operator+' not implemented in type 'database' arguments of type 'int' in function add(database)

it says error @

scanf("%s", test[a].id); 

thanks in advance help, , apolgise if have formatted wrong, still learning use stack overflow, sorry!

this need in order right:

void add(struct database* test) {     printf("\nplease enter 5 digit employee number: ");     scanf("%s",test->id); }  int main() {     ...     int a;     struct database employee[20];     (a=0; a<sizeof(employee)/sizeof(*employee); a++)         add(&employee[a]); // or add(employee+a);     ... }