package test;

import java.util.Scanner;

class Main {
  public static void main(String[] args) {

    while (true) {

      Scanner scn = new Scanner(System.in);
      System.out.print("----------------------------------\n\nif gregorian_to_jalali -> press: g\nor jalali_to_gregorian -> press: j\nor finish -> press: e\n");

      String tabdil = scn.next();
      if ("e".equals(tabdil)) break;

      System.out.print("enter Day: ");
      int day_in = scn.nextInt();
      System.out.print("enter Month: ");
      int month_in = scn.nextInt();
      System.out.print("enter Year: ");
      int year_in = scn.nextInt();

      if ("g".equals(tabdil)) {
        System.out.println("----------------------------------\ngregorian: " + year_in + "-" + month_in + "-" + day_in);
        int[] tarikh_out = DateConverter.gregorian_to_jalali(year_in, month_in, day_in);
        System.out.println("jalali: " + tarikh_out[0] + "/" + tarikh_out[1] + "/" + tarikh_out[2]);
      } else {
        System.out.println("----------------------------------\njalali: " + year_in + "/" + month_in + "/" + day_in);
        int[] tarikh_out = DateConverter.jalali_to_gregorian(year_in, month_in, day_in);
        System.out.println("gregorian: " + tarikh_out[0] + "/" + tarikh_out[1] + "/" + tarikh_out[2]);
      }
      
    }

  }
}




class DateConverter {

  /**  Gregorian & Jalali (Hijri_Shamsi,Solar) Date Converter Functions
  Author: JDF.SCR.IR =>> Download Full Version :  http://jdf.scr.ir/jdf
  License: GNU/LGPL _ Open Source & Free :: Version: 2.80 : [2020=1399]
  ---------------------------------------------------------------------
  355746=361590-5844 & 361590=(30*33*365)+(30*8) & 5844=(16*365)+(16/4)
  355666=355746-79-1 & 355668=355746-79+1 &  1595=605+990 &  605=621-16
  990=30*33 & 12053=(365*33)+(32/4) & 36524=(365*100)+(100/4)-(100/100)
  1461=(365*4)+(4/4) & 146097=(365*400)+(400/4)-(400/100)+(400/400)  */

  public static int[] gregorian_to_jalali(int gy, int gm, int gd) {
    int days, jm, jd;
    {
      int gy2 = (gm > 2) ? (gy + 1) : gy;
      int[] g_d_m = { 0, 31, 59, 90, 120, 151, 181, 212, 243, 273, 304, 334 };
      days = 355666 + (365 * gy) + ((int) ((gy2 + 3) / 4)) - ((int) ((gy2 + 99) / 100)) + ((int) ((gy2 + 399) / 400)) + gd + g_d_m[gm - 1];
    }
    int jy = -1595 + (33 * ((int) (days / 12053)));
    days %= 12053;
    jy += 4 * ((int) (days / 1461));
    days %= 1461;
    if (days > 365) {
      jy += (int) ((days - 1) / 365);
      days = (days - 1) % 365;
    }
    if (days < 186) {
      jm = 1 + (int)(days / 31);
      jd = 1 + (days % 31);
    } else {
      jm = 7 + (int)((days - 186) / 30);
      jd = 1 + ((days - 186) % 30);
    }
    int[] jalali = { jy, jm, jd };
    return jalali;
  }

  public static int[] jalali_to_gregorian(int jy, int jm, int jd) {
    jy += 1595;
    int days = -355668 + (365 * jy) + (((int) (jy / 33)) * 8) + ((int) (((jy % 33) + 3) / 4)) + jd + ((jm < 7) ? (jm - 1) * 31 : ((jm - 7) * 30) + 186);
    int gy = 400 * ((int) (days / 146097));
    days %= 146097;
    if (days > 36524) {
      gy += 100 * ((int) (--days / 36524));
      days %= 36524;
      if (days >= 365)
        days++;
    }
    gy += 4 * ((int) (days / 1461));
    days %= 1461;
    if (days > 365) {
      gy += (int) ((days - 1) / 365);
      days = (days - 1) % 365;
    }
    int gm, gd = days + 1;
    {
      int[] sal_a = { 0, 31, ((gy % 4 == 0 && gy % 100 != 0) || (gy % 400 == 0)) ? 29 : 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 };
      for (gm = 0; gm < 13 && gd > sal_a[gm]; gm++) gd -= sal_a[gm];
    }
    int[] gregorian = { gy, gm, gd };
    return gregorian;
  }

}