uses crt;
const n=5;
m=6;
var a:array[1..n,1..m] of integer;
i,j:byte;
x:integer;
f:text;
begin
clrscr;
randomize;
assign(f,'matrica.txt');
rewrite(f);
writeln('Исходная матрица:');
writeln(f,'Ishodnaya matrica:');
for i:=1 to n do
begin
for j:=1 to m do
begin
a[i,j]:=random(50)-25;
write(a[i,j]:5);
write(f,a[i,j]:5);
end;
writeln;
writeln(f,'');
end;
writeln;
writeln(f,'');
for j:=1 to m do
begin
x:=a[2,j];
a[2,j]:=a[4,j];
a[4,j]:=x;
end;
writeln('Обмен строк 2 и 4:');
writeln(f,'Obmen strok 2 i 4:');
for i:=1 to n do
begin
for j:=1 to m do
begin
write(a[i,j]:5);
write(f,a[i,j]:5);
end;
writeln;
writeln(f,'');
end;
close(f);
write('Матрицы записаны в файл MATRICA.TXT');
readln
end.