this is my program:
program Tresh;
const
    SIZE = 1000;
var
    a : array[1..SIZE] of Byte;
    max : array[1..SIZE] of Longint;
    n : Longint;
function MaxFrase (i, cur : Longint) : Longint;
var
    j, curmax, curn : Longint;
begin
    curmax := 0;
    if i+2 > n then begin
        MaxFrase := cur+a[i];
        Exit;
    end;
    if max[i] <> 0 then
        MaxFrase := max[i]
    else begin
        for j := i+2 to n do begin
            curn := MaxFrase(j, cur+a[i]);
            if curn > curmax then
                curmax := curn;
            end;
        max[i] := curmax;
        MaxFrase := curmax;
    end;
end;
var
    ch, chpred : Char;
    cur : Byte;
    i : Longint;
begin
    i := 1;
    FillChar(max, SizeOf(Longint)*SIZE, 0);
    while not Eof do begin
        Read(ch);
        if not (ch in ['a'..'z', 'A'..'Z']) then begin
            if cur <> 0 then begin
                a[i] := cur;
                Inc (i);
            end;
            cur := 0;
        end
        else begin
{            if ch <> chpred then}
            Inc (cur);
            chpred := ch
        end;
    end;
    if cur <> 0 then begin
        a[i] := cur;
        Inc (i);
        cur := 0;
    end;
    n := i-1;
    Writeln (MaxFrase(1, 0))
end.