const
n=5;
var
a:array[1..n,1..n] of integer;
l:boolean;
i,j:integer;
begin
for i:=1 to n do
begin
for j:=1 to n do
begin
a[i,j]:=10-random(20);
write(' ',a[i,j]:3);
end;
writeln();
end;
writeln('--------') ;
l:=false;
i:=1;
while (i<=n)and(l=false) do
begin
if a[i,i]<0 then l:=true
else inc(i);
end;
if l then
for i:=1 to n do
a[i,i]:=0;
writeln('--------') ;
for i:=1 to n do
begin
for j:=1 to n do
begin
write(' ',a[i,j]:3);
end;
writeln();
end;
end.