Var
 S:String;
 W:Array[1..100] of String;
 i,j,Nw,Nsymb:Byte;
 b,b1:boolean;
Begin
 Writeln('Enter the string:');
 Readln(S);
 Nw:=1;
 i:=0;
 W[Nw]:='';
 Repeat
  Inc(i);
  If (S[i]<>' ') and (i<=Length(S)) then
   W[Nw]:=W[Nw]+S[i]
  else
  If S[i]=' ' then
   begin
    Inc(Nw);
    W[Nw]:='';
   end;
 Until i>Length(S);
 Nsymb:=0;
 Repeat
  Inc(Nsymb);
  b:=true;
  b1:=false;
  For i:=1 to Nw do
   If Length(W[i])<Nsymb then b1:=true;
  If Not(b1) then
   For i:=1 to Nw-1 do
    For j:=i+1 to Nw do
     If W[i][Nsymb]=W[j][Nsymb] then b:=false;
 Until b or b1;
 If b1 then
  Writeln('No solution!')
 else
  Writeln('Minimal number of symbols is ',Nsymb);
 Readln
End.