uses crt;
const n=5;
var a:array[1..n,1..n]of integer;
i,j,:integer;
begin
clrscr;
randomize;
writeln('Исходная матрица');
for i:=1 to n do
begin
for j;=1 to n do
begin
a[i,j]:=-20+random(60);
write(a[i,j]:3);
end;
writeln;
end;
for i:=1 to n do for j:=1 to n do if a[i,j]<=0 then a[i,j]:=0 else a[i,j]:=1;
writeln('Нижний треугольник');
for i:=1 to n do
begin
for j:=1 to i do write(a[i,j]:3);
writeln;
end;
readln;
end.