Помогите разобраться почему не работает пузырьковая сортировка
program lr1;
uses crt;
var
nf: file of integer;
n:array [1..50] of integer;
z,g,s: integer;
A:integer;
begin
for z:= 1 to 50 do
Begin
n[z]:= Trunc(Random*100)-0;
Write(n[z], ' | ')
end;
assign(nf, 'D:\data.txt');
rewrite(nf);
for z:= 1 to 50 do write(nf, n[z]);
writeln('Ïîëó÷åííûé ôàéë');
While not Eof(nf) do
for z:=1 to 50 do
Begin
read(nf,n[z]);
writeln(n[z]);
End;
readln;
close(nf);
For z := 1 To g-1 Do
For A := 1 To g-1 Do
If n > n[s+1] Then
Begin
A:=n[z];
n[z]:=n[z+1];
n[z+1]:=A
End;
Writeln('Îòñîðòèðîâàííûé ìàññèâ ÷èñåë:');
For z:=1 To 50 Do
Write (n[z], ' | ');
End.