var a,b,c: integer;

begin

write('Nhap ngay'); read(a);

write('Nhap thang'); read(b);

write('Nhap nam'); read(c);

write('Ngay',a,'Thang',b,'Nam',c);

end.

#include <bits/stdc++.h>
using namespace std;
bool laNamNhuan(int nYear)
{
 if ((nYear % 4 == 0 && nYear % 100 != 0) || nYear % 400 == 0)
 {
  return true;
 }
 return false;
}
int tinhSoNgayTrongThang(int nMonth, int nYear)
{
 int nNumOfDays;

 switch (nMonth)
 {
 case 1:case 3:case 5:case 7:case 8:case 10:case 12:
  nNumOfDays = 31;
  break;
 case 4:case 6:case 9:case 11:
  nNumOfDays = 30;
  break;
 case 2:
  if (laNamNhuan(nYear))
  {
   nNumOfDays = 29;
  }
  else
  {
   nNumOfDays = 28;
  }
  break;
 }
 return nNumOfDays;
}
bool laNgayHopLe(int nDay, int nMonth, int nYear)
{
 bool bResult = true;
 if (!(nYear > 0 && nMonth))
 {
  bResult = false;
 }
 if (!(nMonth >= 1 && nMonth <= 12))
 {
  bResult = false;
 }
 if (!(nDay >= 1 && nDay <= tinhSoNgayTrongThang(nMonth, nYear)))
 {
  bResult = false;
 }
 return bResult;
}
void timNgayHomSau(int& nDay, int& nMonth, int& nYear)
{
 nDay++;
 if (nDay > tinhSoNgayTrongThang(nMonth, nYear))
 {
  nDay = 1;
  nMonth++;
  if (nMonth > 12)
  {
   nMonth = 1;
   nYear++;
  }
 }
}
int main()
{
 int nDay, nMonth, nYear;
 cout << “Ngay: “;
 cin >> nDay;
 cout << “Thang: “;
 cin >> nMonth;
 cout << “Nam: “;
 cin >> nYear;
 if (laNgayHopLe(nDay, nMonth, nYear))
 {
  int tmpDay = nDay;
  int tmpMonth = nMonth;
  int tmpYear = nYear;
  timNgayHomSau(tmpDay, tmpMonth, tmpYear);
  cout << “Ngay hom sau: ” << tmpDay << ” / ” << tmpMonth << ” / ” << tmpYear;
 }
 else
 {
  cout << “Khong hop le.” << endl;
 }
    //samon247
 return 0;
}