De&Dap an Tin hoc

Bài 1Var i,n:integer; s:longint; Function nta:integer:boolean; Var b,dem:integer; Begin.

Bài 1

Var i,n:integer;

s:longint;

Function nt(a:integer):boolean; Var b,dem:integer;

Begin

For b:=1 to a do

if a mod b = 0 then dem:=dem+1;

if dem = 2 then nt:=true

else nt:=false;

End;

BEGIN

Write('Nhap N: '); Readln(n);

If ((n mod 2) <> 0) then

for i:= 2 to n do

if nt(i) then s:=s+i;

if n mod 2 = 0 then

for i:=1 to n do

if (i mod 2) <> 0 then s:=s+i*i;

Writeln('Tong S=',s);

readln;

END

Bài 2

Var

i,j,k,n,x,y,z,dem: integer;

BEGIN

Write('Nhap so tien can rut ( n<= 10000): '); readln(n);

Write('Nhap 3 loai tien ma may co (x,y,z<=500) : '); readln(x,y,z);

For i:=0 to n div x do

for j:=0 to n div y do

for k:=0 to n div z do

if i*x +j*y +k*z = n then

begin

Dem:=dem+1;

Writeln('Cach ',dem,': So tien loai ',x,'; ',y,'; ',z,'; lan luot la: ',i*x,'; ',j*y,'; ',k*z,'.');

end;

if dem= 0 then Write('Khong co cach nao de rut dung so tien yeu cau') else Writeln('Co tat ca ',dem,' cach rut tien');

readln;

END

Bài 3

uses crt;

Var

i,t,k1,k2: integer;

j,g: char;

s1,s2: String;

BEGIN

Write('Nhap xau ky tu : '); Readln(s1);

For i:=1 to length(s1) do

For j:='A' to 'Z' do

Begin

if j=s1[i] then

begin

t:= (k1+5) mod 26;

k2:=0;

for g:='A' to 'Z' do

begin

if k2=t then s2:=s2+g; k2:=k2+1;

end;

end;

k1:=k1+1;

end;

Write(' Xau ky tu tren duoc ma hoa la: ',s2); Readln;

END