Program n1;
var n,i: integer;
p: real;
begin
p:=1;
readln(n);
for i:=1 to n do p:=p*i;
writeln(p);
end.
Program n1;
var n,i: integer;
p: real;
begin
p:=1;
readln(n);
for i:=1 to n do p:=p*i;
writeln(p);
end.