void lab_avg(struct student_struct student1[],int size)
{
   int i,j,avg;

/*12 could be input argument..*/

for (i=0;i<size;i++) {
   avg=0;
   for (j=1;j<12;j++) {
      avg += student1[i].labs[j];
   }
   student1[i].labavg = (float)avg/12;
}
}