$@Elaina2k4$

`1.` uses crt;

var a,b,c,d,max:integer;

begin

clrscr;

write('Nhap a='); readln(a);

write('Nhap b='); readln(b);

write('Nhap c='); readln(c);

write('Nhap d='); readln(d);

writeln('Tong cua 4 so la: ',a+b+c+d);

max:=a;

if max<b then max:=b;

if max<c then max:=c;

if max<d then max:=d;

writeln('Gia tri lon nhat la: ',max);

readln;

end.

`2.`

Program viet_chuong_trinh_tinh_tong;
Uses Crt; 
Var i,s:integer; 
Begin 
Clrscr; 
i:=5; 
While (i>1) and (i<=100) do 
Begin 
s:=s+i; 
i:=i+5; 
End; 
Writeln(S); 
Readln; 

C1:

uses crt;

var a,b,c,d,max:integer;

begin

write('nhap a:');readln(a);

max:=a;

write('nhap b:');readln(b);

write('nhap c:');readln(c);

write('nhap d:');readln(d);

if max<b then max:=b;

if max<c then max:=c;

if max<d then max:=d;

writeln('So lon nhat la: ',max);

readln;

end.

C2:

uses crt;

var n,i,S:integer;

begin

write('nhap n:');readln(n);

S:=0;

for i:=1 to n do if (i mod 5)=0 then S:=S+i;

writeln('Tong cac so c hia het cho 5 la: ',S);

readln;

end.