C program - sort Big than small

i/p : 1 2 7 8
o/p : 8 1 7 2

#include<stdio.h>
void sort(int* a,int n){
//bubble sort
//i/p : *a - array is passed as reference && n -no of terms
 int temp,i,j;
 for(i=0;i<n;i++){
  for(j=0;j<n;j++){
   if(a[i] < a[j]){
    temp=a[j];
    a[j]=a[i];
    a[i]=temp;
   }
  }
 }
}
int main(){
 int a[10],n,i,cnt_var,l=0,m;// l -> to points the first element in array
 printf("Enter the n terms : ");
 scanf("%d",&n);
 printf("Enter the array elements : ");
 for(i=0;i<n;i++)
  scanf("%d",&a[i]);
 //call sort function to sort the array (! array is passed as reference )
 sort(&a,n);
 //cnt_var -> control variable of the loop
 cnt_var=0;
 //m -> to points the last position in array
 m=n-1;
 //logic is for every even number if stmt is executed
 //odd number -> else stmt is executed
 while(cnt_var < n){
  if((cnt_var%2) == 0){
   printf("%d\t",a[m]);
   m--;
  }else{
   printf("%d\t",a[l]);
   l++;
  }
  cnt_var++;
 }
 return 0;
} 

any doubts comment below