Insertion Sort in C++

#include <stdio.h>
/* Insertion Sort in C++ */

void sort(int arr[], int size) {
   
   for(int i = 0; i < size; ++i) {
       // Set a temp of the current variable
       int tmp = arr[i];
       int j = i - 1;
       // While j is out of place in the array, iterate backwards.
       while(j >= 0 && arr[j] > tmp) {
           arr[j+1] = arr[j];
           j -= 1;
       }
       // Assign the correct location of i where j stops.
       arr[j+1] = tmp;
   }
}

// Demo:
int main() {
   // Test array:
   int a[] = {4, 8, 5, 1, 2, 0, 9};
   // Get the number of elements in the array:
   int s = sizeof(a) / sizeof(a[0]);

   // Sort the array:
   sort(a, s);

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

   return 0;
}