var
m:char;
a,b,j,k:integer;
c:real;
begin
readln(m);
if m='a' then
begin
readln(a);
readln(b);
c:= a/b - a div b;
writeln(c:4:2);
end;
if m='b' then
begin
j:=1;
k:=1;
while k < 22 do
begin
j := j*k;
k:= k+1;
end;
writeln(j);
end;
if m='c' then
begin
j:=0;
k:=10;
while k <= 50 do<br>begin
j := j+k;
k:= k+1;
end;
writeln(j);
end;
readln;
end.