C++ :

#include<iostream>
using namespace std ;
int main ()
{
	float a=0,x=0;
	while(a<=99)
	{
		a++;
		x=x+1/a;
	}
	printf("%0.3f\n",x);
	return 0;
}	

Pascal :

var a,b,c:longint;
e,d:real;
begin
 read(a);c:=0;
 d:=0;
 for b:=1 to 100 do
 begin
 c:=c+1;
 e:=1/c;
 d:=d+e;
 end;
 writeln(d:0:3);
end.