#include<stdio.h>
#include<math.h>
int main()
{
    double a,b,c,d,e,f,g,h,i,j,result;
    scanf("%lf %lf %lf %lf %lf %lf %lf %lf %lf %lf",&a,&b,&c,&d,&e,&f,&g,&h,&i,&j);
    result = sqrt(a+b+c+d+e+f+g+h+i+j);
    printf("%.1lf",result);
    return 0;
}