Исправить ошибку: "Cannot convert "STUDENTS**" to int" - C (СИ)

#include <stdio.h>
#include <conio.h>
#include<alloc.h>        
#include <string.h>
#define kstud 10

typedef struct {int day; int month; int year;} DATE;
typedef struct {char *name;char gender;int sumball;DATE born;} STUDENTS;

void vvod(STUDENTS group[],STUDENTS *Ukazatelgroup[],int  number)
 
 {  
     int i;

     printf("Vvod dannix gruppi studentov:\n");
     for (i=0; i<number; i++)
       {    printf ("%2d.",i+1);
        fflush (stdin);
 
            printf("Vvedite Familiu Imia i Otchestvo studenta: ");

        (group+i)->name=(char*)malloc(31);
         gets((group+i)->name);
         fflush (stdin);

        printf("Vvedite pol(m ili w ): ");
        scanf("%c",&(group+i)->gender);
        
            printf ("Data rogdeniya?(day_month_year): ");
        fflush (stdin);
        scanf("%i%i%i",&(group+i)->born.day,&(group+i)->born.month,&(group+i)->born.year);

        printf ("Summarnei ball?: ");
        scanf("%d",&(group+i)->sumball);
        fflush (stdin);
        Ukazatelgroup[i]=group+i;

     }
}

void vivod(STUDENTS *group[], int number)
{ 
  int i;
  puts("Student:   Pol: Sumball:     Data rozdenia:  ");
  for (i=0;i<number;i++)
  printf ("%d%-12s%-6c%-12i%-4i%-4i%-4i\n",i+1,group[i]->name,group[i]->gender,group[i]->sumball,group[i]->born.day, group[i]->born.month, group[i]->born.year);
  free (group[i]->name);

}     
 
int filter(STUDENTS *pStudents[], STUDENTS *pSortedStudents[],int number) 
{
  int i,nmb=0 ;
  for (i=0;i<number;i++)
   {  if( (pStudents[i]->sumball == 9) && ( pStudents[i]->gender == 'm'  ))
      { pSortedStudents[nmb] = pStudents[i];
        nmb = nmb + 1;
      }
   } 
  return nmb;
}

void main()
 {
     int ks;
     STUDENTS group[kstud];
     STUDENTS *Ukazatel_filtered_group[kstud];
     STUDENTS *Ukazatelgroup[kstud];
     int filtered_nmb = 0;
 
     printf("Vvedite kolichestvo studentov v gruppe(ne bolshe 10!):\n");
     scanf("%i",&ks);
 
     vvod(group,Ukazatelgroup,ks);
   
     printf("Dannie studentov:\n");
 
     vivod(Ukazatelgroup,ks);
 
     filtered_nmb=filter(Ukazatelgroup,Ukazatel_filtered_group,ks);
     int filter(Ukazatelgroup,Ukazatel_filtered_group,ks);    
   [COLOR=Red] // Cannot  convert"STUDENTS**" to int
                       //   } expected[/COLOR]
     printf("Spisok bez sortirovki:\n");
     vivod(Ukazatel_filtered_group,filtered_nmb);

}