uses crt;
const nmax=20;
var a:array[1..nmax,1..nmax] of integer;
m,n,i,j,k:byte;
s:real;
begin
clrscr;
randomize;
repeat
write('Количество строк до ',nmax,' n=');
readln(n);
until n in [1..nmax];
repeat
write('Количество столбцов до ',nmax,' m=');
readln(m);
until m in [1..nmax];
writeln('Исходная матрица:');
for i:=1 to n do
begin
for j:=1 to m do
begin
a[i,j]:=random(10);
write(a[i,j]:3);
end;
writeln;
end;
writeln;
k:=0;
for j:=1 to m do
begin
s:=0;
for i:=1 to n do
s:=s+a[i,j];
s:=s/n;
writeln('В столбце ',j,' среднее=',s:0:2);
if s<=4.5 then k:=k+1;
end;
write('Количество столбцов со средним <=4.5=',k);
readln
end.