간단한 C언어 파일 입출력 질문입니다

#include <stdio.h>
#define size 10
 
typedef struct employee
{
   char name[10];
   int empno;
   int income;
}EMPLOYEE;
float average(EMPLOYEE e[], int n);
 
int main(void)
 
{
   FILE *infp, *outfp;
   int i;
   float ave;
   EMPLOYEE emp[size];
   fopen_s(&infp, "employee.txt", "r");
   fopen_s(&outfp,"out.txt", "w");
   for (i=0;i<size;i++)
 
   {
      fscanf_s(infp, "%s %d %d", emp[i].name, &emp[i].empno, &emp[i].income);
   }
 
   ave = average(emp,i);
 
   fprintf(outfp, "----------------------------------------\n");
   fprintf(outfp, "이름\t사원번호\t급여\n");
   fprintf(outfp, "----------------------------------------\n");
 
   for (i = 0; i < size; i++)
   {
      if (emp[i].income >= ave)
         fprintf(outfp, "%s\t%d\t%d\n", emp[i].name, emp[i].empno, emp[i].income);
   }
 
   fclose(infp);
   fclose(outfp);
   return 0;
 
}
 
float average(EMPLOYEE e[], int n)
{
   float sum = 0;
   int i;
   for (i = 0; i < n; i++)
      {
         sum += e[i].income;
 
      }
      return (sum / n);
 
}