import java.util.*;
import java.lang.*;
import java.io.*;
class Ideone
{
{
Scanner in
= new Scanner
(System.
in); double S=0, m, n;
m=in.nextInt();
n=in.nextInt();
for(int i=1;i<=m;i++){
for(int j=1;j<=n;j++){
S+=1.0/(i+j*j);
}
}
}
}
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