program ZADACHA4;
var
a : array [1..15] of integer;
I : byte;
z,y,w,h,k : integer;
begin
  Randomize;
z:=50;
h:=0;
For i := 1 to 15 do
  Begin
    a[i]:=-20+random(50-(-20+1));
    if a[i] < z then
      begin
        z := a[i];
        w := i;
      end;
    h := a[i] + h;
  end;
writeln('Massiv do: ',a);
k:=trunc(h/15);
writeln;
writeln('Srednee arifmetichskoe vsego massiva: ', k);
writeln;
writeln('Minimalni element v massive: ', z);
for i := 1 to 15 do
  if a[i] = k then
    begin
      y := i;
      break
    end;
a[y] := z;
a[w] := k;
writeln;
writeln('Massiv posle: ',a);
end.