Var s: string[100];
i: byte;
Begin
Write('nhap xau: '); readln(s);
While s[1]=' ' do delete(s, 1, 1);
While s[length(s)]=' ' do
delete(s, length(s), 1);
I:=1;
While i<length(s) do
Begin
If (s[i]=' ') and (s[i+1]=' ') then
Begin
Delete(s, i, 1); dec(i);
End;
Inc(i);
End;
Write(s);
Readln
End.