#include<stdio.h>
int main() {
    float sum = 0;
    int count = 0;
    int temp;
    while(scanf("%d",&temp) == 1) {
        sum += temp;
        count++;
    }
    
    if(count == 0)
    {
      printf("No readings provided");
    }
    else {
     float count = sum /avg;
     printf("%.2f",count);
    }
    return 0;
}