в двумерном массиве анйти отрицательные числа

Program L7;
Uses crt;
Var
mas:array [1..5,1..5] of integer;
i,j,l,n,m:integer;
Begin
clrscr;
randomize;
write('wedite n:');
read(n);
write('wwedite m:');
read(m);
 for i:=1 to n do
  begin
for j:=1 to m do
mas[i,j]:=random(10)-random(10);
end;
writeln('wwedenniy massiv :');
for i:=1 to n do
 begin
 for j:=1 to m do
 writeln(mas[i,j]);
 read;
 end;
for i:=1 to n do
begin
for j:=1 to m do
begin
if mas[i,j]<0 then
begin
mas[i,j]:=0;
readln;
   end;
    end;
   begin
for i:=1 to n do
begin
for j:=1 to m do
begin
if mas[i,j]>=0 then
writeln(mas[i,j]);
readln;
readkey;
end;
End;
end;
end;
end.

Program maxim;
Uses crt;
 var b:array [1..100,1..100] of integer;
     i,j,n:integer;
begin
clrscr;
 Writeln (' vvedite razmernost matrici ');
 Readln (n);
  for i:=1 to n do
    for j:=1 to n do begin
                     write ('B[',i,',',j,']=');
                     Readln (b[i,j]);
                     end;
writeln (' Polychena matrica ');
for i:=1 to n do
 begin
 for j:=1 to n do
    Write ('  ',b[i,j],' ');
    writeln;
 end;
writeln;
 for i:=1 to n do
     for j:=1 to n do
      if b[i,j]<0 then b[i,j]:=0;
writeln (' OTBET ');
for i:=1 to n do
 begin
 for j:=1 to n do
    Write ('  ',b[i,j],' ');
    writeln;
    end;
Readln
end.