Program tong_so_chan; Uses crt; Var S,N,I:Integer; Begin Clrscr; Write('Nhap N ');Readln(N); S:=0; For I:=1 to N do If (I mod 2=0) then S:=S+I; Writeln('Tong cac so chan la ',S); Readln; End.
uses crt; var n,i,s:longint; begin clrscr; write('Nhap n (n>0): '); readln(n); for i:=1 to n do if i mod 2=0 then inc(s,i); writeln('Tong: ',s); readln; end.
