var
 S:string;
 f1,f2:text;
 b:boolean;

function Lit(C:Char):boolean;
begin
 Lit:=((ord(C)>64) and (ord(C)<91)) or
      ((ord(C)>96) and (ord(C)<123));
end;

function BeginOfLine(S:string):string;
var
 O:string;
begin
 O:=S;
 while not(Lit(O[1])) do
  begin
   delete(O,1,1);
   b:=false;
  end;
 BeginOfLine:=O;
end;


function DelProbBefCh(S:string):string;
var
 P:string;
 i:integer;
begin
 P:=S;
 i:=1;
 repeat
  if (P[i]=' ') and (P[i+1]=' ') then
   begin
    delete(P,i+1,1);
    b:=false;
   end
   else i:=i+1;
 until i=length(P)-1;
  DelProbBefCh:=P;
end;

function DelNextSimb(S:string):string;
var N:string;
i:integer;
begin
 i:=1;
 N:=S;
 while i<=(length(N)-1) do
  begin
   if Not(Lit(N[i])) and Not(Lit(N[i+1])) and (N[i+1]<>' ') then
    begin
     delete(N,i+1,1);
     b:=false;
    end else i:=i+1;
  end;
  DelNextSimb:=N;
end;

function InsProb(S:string):string;
var
 M:string;
 i:integer;
begin
 M:=S;
 i:=1;
 repeat
  if Not(Lit(M[i])) and (M[i]<>' ') and Lit(M[i+1]) then
   begin
    insert(' ',M,i+1);
    b:=false;
    i:=i+1;
   end;
  i:=i+1;
 until i=length(M)-1;
 InsProb:=M;
end;

begin
  assign(f1, 'Input.txt');
  reset(f1);
  assign(f2, 'Output.txt');
  rewrite(f2);
  while not eof(f1) do
  begin
    readln(f1,S);
    repeat
     b:=true;
     S:=BeginOfLine(S);
     S:=DelProbBefCh(S);
     S:=DelNextSimb(S);
     S:=InsProb(S);
    until b;
    writeln(f2,S);
  end;
  close(f1);
  close(f2);
end.