#include <stdio.h>
#include <stdlib.h>
#include <stdbool.h>

int main(void)
{
    int data_num;
    scanf("%d",&data_num);

    int *data_array;
    data_array = (int *)malloc( sizeof(int)*data_num );

    int i=0;
    for( ; i<data_num; i++)
        scanf("%d", &data_array[i]);

    for( i=0; i<data_num-1; i++)
    {
        int j=0;
        bool swapped = false;
        for( j=0; j<data_num-i-1; j++)
        {
            if(data_array[j] > data_array[j+1])
            {
                int tmp = data_array[j];
                data_array[j] = data_array[j+1];
                data_array[j+1] = tmp;
                swapped = true;
            }
        }
        if(!swapped)
        	break;
    }
    
    if(data_num%2==1)
    	printf("%d\n", data_array[data_num/2]);
    else
    	printf("%2.1f\n", (float)((data_array[data_num/2-1]+data_array[data_num/2]))/2.0);
}