Ошибка в коде

uses crt;
const n=5;
type vec=array [1..10] of integer;
     mtr=array [1..10]of vec;
procedure read_file(var f:text;var s:string;var a:mtr;var m,n:integer);
var st:string;
    x,i,j:integer;
begin
writeln('Vvedite imia dlia chteniaя');
readln(s);
assign(f,s);
{$I-}
reset(f);
{$I+}
if IOResult<> 0 then
 begin
  writeln('Fail ne naiden');
  readln;
  halt;
 end;
m:=0;
while not seekeof(f)do
 begin
  readln(f,st);
  m:=m+1;
 end;
reset(f);
n:=0;
while not eoln(f) do
 begin
  read(f,x);
  n:=n+1;
 end;
reset(f);
 
for i:=0 to m-1 do
for j:=0 to n-1 do
read(f,a[i,j]);
close(f);
end;
function max_vec(v:vec;n:integer):integer;
var i,mx:integer;
begin
mx:=abs(v[1]);
for i:=1 to n-1 do
if abs(v[i])>mx then mx:=abs(v[i]);
max_vec:=mx;
end;
procedure sort_vec(var a:mtr;m,n:integer);
var i,j:integer;
    x:vec;
begin
for i:=0 to m-2 do
for j:=i+1 to m-1 do
if max_vec(a[i],n)>max_vec(a[j],n)then
 begin
  x:=a[i];
  a[i]:=a[j];
  a[j]:=x;
 end;
end;
procedure write_file(a:mtr;m,n:integer;var f:text; var s:string);
var i,j:integer;
begin
writeln('Vvedite imia faila dlia zapisi');
readln(s);
assign(f,s);
rewrite(f);
for i:=0 to m-1 do
 begin
  for j:=0 to n-1 do
  write(f,a[i,j]:5);
  writeln(f);
 end;
close(f);
end;
 
var f:text;
    a:mtr;
    m:integer;
    name1,name2:string;
begin
clrscr;
read_file(f,name1,a,m,n);
sort_vec(a,m,n);
write_file(a,m,n,f,name2);
writeln('Fail ',name1,' prochitan, vectora otsortirovani i zapisani v fail ',name2);
readln;
end.

var f:text;
     a:mtr;
     n,m:integer;
     name1,name2:string;