Не запускает програму

program algoritm;
uses crt;
var i,des,n,l,dva,delo:integer;
s,dvaS,s2:string;
begin
Writeln('Vvedite shestnadtsatichnoe chislo:');
read(s);
l:=length(s);
for i:=1 to length(s) do
begin
if (s[i]>#47) and (s[i]<#58) then 
begin
dva:=StrToInt(s[i]);
if dva=0 then s2:='0000';
if dva=1 then s2:='0001';
if dva=2 then s2:='0010';
if dva=3 then s2:='0011';
if dva=4 then s2:='0100';
if dva=5 then s2:='0101';
if dva=6 then s2:='0110';
if dva=7 then s2:='0111';
if dva=8 then s2:='1000';
if dva=9 then s2:='1001';
end
else 
begin
if s[i]='A' then s2:='1010';
if s[i]='B' then s2:='1011';
if s[i]='C' then s2:='1100';
if s[i]='D' then s2:='1101';
if s[i]='E' then s2:='1110';
if s[i]='F' then s2:='1111';
end;
dvaS:=dvaS+S2;
end;
Writeln('Dvoichnoe chislo: ',dvaS);
end.

var dva:char;
..............
for i:=1 to length(s) do
begin
if s[i]in ['0'..'9'] then
begin
if dva='0' then s2:='0000';
if dva='1' then s2:='0001';
if dva='2' then s2:='0010';
if dva='3' then s2:='0011';
if dva='4' then s2:='0100';
if dva='5' then s2:='0101';
if dva='6' then s2:='0110';
if dva='7' then s2:='0111';
if dva='8' then s2:='1000';
if dva='9' then s2:='1001';

if s[i]in ['0'..'9'] then

uses crt;
var s1,s2:string;
    a,b,c:array[byte] of 0..1;
    n,m,i,j,p:byte;
    k:integer;
begin
clrscr;
repeat
p:=0;
write('Введите число A в СС 2:');
readln(s1);
i:=1;
while(i<=length(s1))and(p=0) do
if not(s1[i] in ['0','1']) then p:=1
else i:=i+1;
until p=0;
repeat
p:=0;
write('Введите число B в СС 2:');
readln(s2);
i:=1;
while(i<=length(s2))and(p=0) do
if not(s2[i] in ['0','1']) then p:=1
else i:=i+1;
until p=0;
if length(s1)<length(s2) then
while length(s1)<length(s2) do
s1:='0'+s1
else if length(s1)>length(s2) then
while length(s2)<length(s1) do
s2:='0'+s2;
writeln('  ',s1);
writeln(' +');
writeln('  ',s2);
for i:=1 to length(s1)+2 do
write('-');
writeln;
n:=length(s1);
m:=n;
for i:=1 to n do
 begin
  val(s1[i],a[i],k);
  val(s2[i],b[i],k);
 end;
p:=0;
for i:=n downto 1 do
  begin
   c[i]:=a[i]+b[i]+p;
   if (c[i]>1)and(i>1) then
      begin
       c[i]:=c[i] mod 2;
       p:=1;
      end
    else p:=0;
  end;
if c[1]>1 then
  begin
    c[1]:=c[1] mod 2;
    n:=n+1;
    for j:=n downto 2 do
    c[j]:=c[j-1];
    c[1]:=1;
  end;
if n=m then write('  ')
else write(' ');
for i:=1 to n do
write(c[i]);
readln
end.