uses crt;
const t=7;
var A:array[1..10] of integer;
i,tong:integer;
begin
clrscr;
for i:=1 to 10 do
begin
write('Nhap phan tu thu ',i,': ');
readln(A[i]);
if i mod 2 = 0 then tong:=tong+A[i];
end;
for i:=10 downto 1 do write(A[i]:4);
writeln;
write('A[5]=',A[5]);
writeln;
write('Cac chi so co gia tri phan tu bang 7: ');
for i:=1 to 10 do if A[i]=7 then write(i:4);
writeln;
for i:=1 to 10 do if i mod 2 = 0 then write(A[i]:4);
writeln;
write('Tong cua chung la: ',tong);
readln
end.