#include <stdio.h>
void average(int *quantity,int number,double *avr)
{
int i,sum=0;
for(i=0;i<number;i++) sum+= *(quantity+i);
*avr = ((double) sum)/((double) number);
}
int main(void)
{
int quantity[]={1, 4, 2, 8, 1, 5};
double avr;
average(quantity,6,&avr);
printf("%f\n",avr);
return(0);
}