mean value in the middle

#include "StdAfx.h"
#include <stdio.h>
#include <malloc.h>
#include <stdlib.h>

int main(){
int *a;
int i,n, s=0,sr;

printf("Enter the size : ");
scanf_s("%d", &n);
a = (int*)malloc(n * sizeof(int));

for (i = 0; i < n; i++)
{
printf("a[%d] = ", i);
scanf_s("%d", &a[i]);
s += a[i];
}

sr =int(s / n);
printf("%d", sr);

n = n + 1;
a = (int*)realloc(a,n * sizeof(int));

for (i = n; i > n / 2; i--){
a[i] = a[i - 1];
}
a[n / 2] = sr;
printf("\nResult\n");
for (i = 0; i < n; i++){
printf("a[%d] = %d ", i, a[i]);
}
return 0;
}