#include <stdio.h>
#include <math.h>
int main()
{
double n = 0.00;
int m = 0;
while (~scanf("%lf %d", &n, &m))
{
double sum = 0.00;//这里不能用float,只能用double
for (int i = 0; i < m; i++)//控制m次
{
sum += n;
n = sqrt(n);
}
printf("%.2lf\n", sum);
}
return 0;
}