помогите пожалуйста в Pascal c 3 по 7

Program lol (input, output);
var a, n, b, i, p,s, m:integer;
c:real;
begin
read (n);
a:=n;
b:=0;
c:=0;
p:=1;
while a lt;gt; 0 do
begin
a:=a div 10;
b:=b+1;
end;
while b lt;gt; 0 do
begin
p:=1;
for m:=1 to b do
p:=p*10;
s:=(n mod p) div (p div 10);
c:=c+s;
end;
b:=b-1;
end;
writeln (c);
end.
---------------------------------------------------
program lol (input, output);
var I, a:integer;
begin
a:=0;
for I:=31 to 55 do
begin
if (i mod 2) lt;gt; 0 then
a:=a+I;
end;
writeln (a);
end.
------------------------------------------------------

var a, b, c, s, I:integer;
begin
read (a, b);
if alt;b then
begin
c:=a;
a:=b;
b:=c;
end;
c:=a;
while c gt; 0 do
begin
while c gt;= b do
begin
c:=a-b;
if c gt; 0 then
s:=c;
a:=c;
end;
a:=b;
b:=c;
end;
writeln (s);
end.
------------------------------------------------
program lol (input, output);
var m, n, prod: word;
begin
readln(m, n);
prod := m * n;
while m lt;gt; n do
begin
if m gt; n then
begin
m := m - n
end
else
begin
n := n - m
end
end;
writeln(prod div m)
end.
---------------------------------------------
program lol (input, output);
var a, b, c, e:Integer;
d:real;
begin
read (a, b);
d:=a/b;
c:=trunc(d);
e:=a-(b*c);
writeln ('Приватное: ',c);
writeln ('Остаток: ',e);
end.