При переводе диагональной матрицы в вектор приписывается большое количество ненужных нулей

program DiagonalMatrixOlegTsoy;
 
const
  nmax = 20;
 
type
  arr = array of array of integer;
 
var
  n, i, j, t, x, k, k1: integer;
  found: boolean;
 
procedure printout(s: arr);
var
  i, j: integer;
begin
  for i := 0 to high(s) do
  begin
    for j := 0 to high(s[i]) do
    begin
      Write(s[i, j]);
      Write(' ');
    end;
    Writeln();
  end;
end;
 
function g: arr;
var
  i, j: integer;
  s: arr;
begin
  Write('Size of Matrix: '); Readln(n);
  SetLength(s, n);
  for i := 0 to n - 1 do
  begin
    SetLength(s[i], n);
    for j := 0 to n - 1 do
    begin
      if j = i then
        s[i, j] := random(76) - 30
      else 
        s[i, j] := 0;
    end;
    g := s;
  end;
end;
 
var 
  a : arr;
  b : array of integer;
 
begin
  a := g();
  printout(a);
  writeln;
  readln;     
  writeln('Vector:');
  setlength(b, sqr(n));
  for i := 0 to pred(n) do
    for j := 0 to pred(n) do
    begin
      b[i * n + j] := a[i, j];
      write(b[i * n + j]:4);
    end;
  writeln;
  found := false;
  write('Please enter the name of element for linear search: ');
  readln(x);
  for i := 0 to pred(sqr(n)) do
    if b[i] = x then begin
      found := true;
      k := i;
    end;
  if found then writeln('The founded element on the ', k, ' position')
  else writeln('This matrix does not have this element');
  writeln;
  for i := 0 to pred(sqr(n)) do
    for j := pred(sqr(n)) downto i + 1 do
      if b[j] < b[j - 1] then
      begin
        t := b[j];
        b[j] := b[j - 1];
        b[j - 1] := t;
        inc(k1);
      end;
  writeln;
  writeln('Linear Search Algorithm: count of comparisons = ', k);
  writeln('                         count of swaps = ', k1);
  readln;
  writeln('Sorted Vector:');
  for i := 0 to Pred(sqr(n)) do write(b[i]:4);
  writeln;
  readln;
end.

setlength(b, n);
  for i := 0 to pred(n) do
   begin
     b[i] := a[i, i];
     write(b[i]:4);
    end;
  writeln;
  found := false;
  write('Please enter the name of element for linear search: ');
  readln(x);
  for i := 0 to pred(n) do
    if b[i] = x then begin
      found := true;
      k := i+1;
    end;
  if found then writeln('The founded element on the ', k, ' position')
  else writeln('This matrix does not have this element');
  writeln;
  for i := 0 to pred(n) do
    for j := pred(n) downto i + 1 do
      if b[j] < b[j - 1] then
      begin
        t := b[j];
        b[j] := b[j - 1];
        b[j - 1] := t;
        inc(k1);
      end;
  writeln;
  writeln('Linear Search Algorithm: count of comparisons = ', k);
  writeln('                         count of swaps = ', k1);
  readln;
  writeln('Sorted Vector:');
  for i := 0 to Pred(n) do write(b[i]:4);
  writeln;
  readln;
end.