//**********************************
// 公歷日期與農歷日期的相互轉換程序 
// 公元1800年1月25日～2101年1月28日
// 請在VC++6.0平臺運行 
//**********************************
#include<stdio.h>
#include<conio.h>
#include<math.h>
#include<stdlib.h>
#include<windows.h>
#include<iostream.h>

struct date{ short year,month,day; }
d1={ 1800,1,25 },//農歷1800正月初一(星期六)
d2={ 2101,1,28 };//農歷2100臘月廿九(未使用)

struct lunarYear //農歷年
{ char run;      //閏月月份(0表示無閏月)
  char ZL[13];   //農歷i月初一對應公歷i月ZL[i]日(廣義)
} Year[2101      //但是ZL[i]的最高位1表示大月0表示小月
      -1800]={4};//農歷1800年閏四月

#define leap(y) !(y%(y%100?4:400)) //公元閏年宏定義

unsigned char days[]={ 0,31,28,31,30,31,30,31,31,30,31,30,31 },
b[]= //農歷1800-2100年大月(30天)小月(29天)閏月數據(hex string)
{
    "adca5aa92bb525bba25bb493b64a5ba9add496ea8a6ed14eea4a6da5b6"
    "545baa4bba45bba82b75a5b654abaa55d526eda4aed495da526daa5655"
    "abb295ba5257aa4b75a95655abaa56ea4a5da92ed965d594adaa56692b"
    "75a5ba64977493b6ca5a69add496da925dd24dda495da9add45a6a4b75"
    "4937692775a5b6545baa2dd526dda49dd495ba525baa5555ab6a937652"
    "57ea4a75a95655abaa55da4a5da92bd925db54abaa56592b75a5ae6497"
    "ec92aed25659abb495da925dd24bba495ba9add4566a4b75492fe9266d"
    "a5aed4566a2db525bba49bb493ba525baa55d5aa6a936ed24eea4a6da9"
    "36d5aaaa55b64a5ba92b75a5ba54abaa55d52a6da5aed495ec926daa56"
    "55abb495ba525bb24b76495769abb455da4a6dc92ee925dda4add4566a"
    "4bb5a5baa4977493b652576a4db5a6da926dd24dda4a5da92dd5aa6a55"
    "b54937692775a5b654abaa55d52a5da5add495ba925daa55d5aa6c95b6"
    "5257724b76c95659abac55da4a5da92dd925bda4abb4555a4b6da5b6649"
    "7f492aed2566a4bb5a5da925dd24bba495ba92bb5aa6a53754937e9266d"
    "a5aed4966a55b52a5ba5abb495ba525baa55d5aa6a95aed256ea4a6ec94"
    "ed9aa6a55b64a5ba92bb945bb64abb455d64a6da5aee416eda26ed25502"
};
short rs[22]={ //農歷1800-2100年111個閏月所形成的110個間距的數據
32198,25072,32079,29168,31350,3554,29118,28494,25464,28215,7608,
27766,3975,30902,28494,21489,28214,7132,27766,3975,25078,28039};

char f(short m,short x)//1月x日相當于m月f日
{
     for(short i=1;i<m;i++)x-=days[i];
     return char(x);   
}

void initial(void)//初始化Year結構數組
{    short i,t,ir=Year[0].run;
     for(short r=1;r<=110;r++)
     {  if(r%5==1)t=rs[r/5];
        ir+=29+t%8;t>>=3;
        Year[(ir-r)/12].run=(ir-r)%12;
     }  lunarYear*p=&Year[0];r=p->run;
     for(t=0,i=0;b[i]!='\0';i+=2,t++)          //hex string
     #define VAL(h) (h<'a'?(h-'0'):(h-'a'+10)) //hex string
         b[t]=16*VAL(b[i])+VAL(b[i+1]);        //hex string
     short M,y=1800,hao=25;//1800年1月25日為正月初一
     for(M=1,i=0;i<3723;i++,M++)
     {   if(M>12+!!r){ M=1;hao-=365+leap(y);y++;r=(++p)->run; }
         t=b[i/8];t>>=i%8; days[2]=28+leap(y);
         if(r==0||M<=r){p->ZL[M]=f(M,hao);if(t%2)p->ZL[M]|=0x80;}
         else if(M>1+r){p->ZL[M-1]=f(M-1,hao);if(t%2)p->ZL[M-1]|=0x80;}
         else {p->ZL[0]=f(r,hao);if(t%2)p->ZL[0]|=0x80;}
         hao+=29+t%2;   }
}

date getSolar(date D)//農歷→公歷
{
     short im,m;im=m=D.month;
     if(im<0){m=-im;im=0;}
     lunarYear*p=&Year[D.year-1800];
     date d;d.year=D.year;
     d.day=(0x7f&p->ZL[im])-1+D.day;
     days[2]=28+leap(d.year);
     while(d.day>days[m])
     { d.day-=days[m];m=m%12+1;if(m==1)d.year++; }
     d.month=m;return d;
}

date getLunar(date d)//公歷→農歷
{
     lunarYear*p=&Year[d.year-1800];
     days[2]=28+leap(d.year);
     short m=d.month;
     d.day-=(p->ZL[m]&0x7f)-1;
     while(d.day<1){
       if(m==0)m=p->run;
       else if(m==1){ m=12;d.year--;p--; }
       else if(p->run==m-1)m=0;
       else m--;
       d.day+=29+(p->ZL[m]<0);
     }
     if(m==0)m=-p->run;
     d.month=m;return d;
}

long total(date a)//公元以來的天數
{
    days[2]=28+leap(a.year);long C,m,x=a.year-1; 
    for(C=a.day,m=1;m<a.month;m++)C+=days[m];
    return 365*x+x/4-x/100+x/400+C;
}

short ok(date d)
{
    short y=d.year,m=d.month,t=d.day,ok=1;
    if(y<1800||y>2100)ok=-1;
    else if(m<1||m>12)ok=0;
    else{days[2]=28+leap(y);
    if(t<1||t>days[m])ok=0;}
    if(total(d)<total(d1))ok=-1;
    return ok;
}

short OK(date D)//若D.month取負值則表示農歷閏月
{
    short Y=D.year,M=D.month,T=D.day;
    if(Y<1800||Y>2100)return -1;
    if(T<=0||T>30)return 0;//排除明顯的非法"日"號
    if(M==0||M>12)return 0;//排除明顯的非法"月"號
    lunarYear* p=&Year[Y-1800];
    if((M<0?-M==p->run?29+(p->ZL[0]<0):0
            :29+(p->ZL[M]<0))<T)return 0;
    return 1;
}

#define BIG(i) p->ZL[i]<0

void gotoxy(int x, int y)
{
    COORD c;
    c.X = x - 1;c.Y = y - 1;
    SetConsoleCursorPosition (GetStdHandle(STD_OUTPUT_HANDLE), c);
}    

int main( )
{    char*xq[]={"日","一","二","三","四","五","六",
                "七","八","九","十","冬","臘" };
     int cho,Y;
     ios::sync_with_stdio( );
     initial();
     Menu:
     do{
         system("cls");
         gotoxy(10, 7-2);cout<<"1.將公歷轉換為農歷";
         gotoxy(10,10-2);cout<<"2.將農歷轉換為公歷";
         gotoxy(10,13-2);cout<<"3.叁百年農歷閏月表";
         gotoxy(10,16-2);cout<<"4.農歷某年大月小月";
         gotoxy(10,19-2);cout<<"0.運行結束返回系統";
         gotoxy(10,23-2);cout<<"選擇: ";
         cho=getch( );
     } 
     while(cho<'0'||cho>'4');
     if(cho=='4')
     {
        gotoxy(10,23);
        cout<<"年份? ";
        {
           int tmp;
           Y=0;
           while(1)
           {
             tmp=getche();
             if(tmp<'0'||tmp>'9')break;
             Y=Y*10+(tmp-'0');
           }
        }
        if(Y<1800||Y>2100)Y=2008;
     }
     system("cls");
     if(cho<='2')cout<<"\n\n\n\n";
     if(cho=='1')
   while(1)
   {  char c; date DT,dt; int o;
      do{ cout<<"公元(yyyy-mm-dd): ";
      cin>>dt.year>>c>>dt.month>>c>>dt.day;//c為分隔符
      o=ok(dt);if(o==-1)goto Menu; }while(o<=0);
      DT=getLunar(dt);//將公歷日期dt轉換為對應的農歷DT
      cout<<"農歷"<<DT.year<<"年"<<(DT.month<0?"閏":"")
          <<abs(DT.month)<<"月"<<DT.day<<"日"
          <<"〔星期"<<xq[total(dt)%7]<<"〕\n"<<endl;
   }
   else if(cho=='2')
   while(1)
   {  char c; date DT,dt; int o;
      do{ cout<<"農歷(YYYY.MM.DD): ";
      cin>>DT.year>>c>>DT.month>>c>>DT.day;//c為分隔符
      o=OK(DT);if(o==-1)goto Menu; }while(o<=0);
      dt=getSolar(DT);//將農歷日期DT轉換為對應的公歷dt   
      cout<<"公元"<<dt.year<<"年"
          <<dt.month<<"月"<<dt.day<<"日"
          <<"〔星期"<<xq[total(dt)%7]<<"〕\n"<<endl;
   }
   else if(cho=='3')
   {  int counter=0,r;lunarYear* p=&Year[1800-1800];
      gotoxy(19,1);cout<<"1800—2100年間農歷閏月列表"<<endl;
      for(int i=0;i<=2100-1800;i++,p++)
       if((r=Year[i].run)!=0)
       {  if(counter++%5==0)cout<<"\n    ";
          cout<<1800+i<<"閏"<<xq[r]<<"月"
              <<(BIG(0)?"大":"小")<<"  ";
       }  getch();goto Menu;
   }
   else if(cho=='4')
   {  int counter=0;lunarYear* p=&Year[Y-1800];
      cout<<"\n\n          農歷"<<Y<<"年大月小月列表\n\n\n\n    ";
      for(int m=1;m<=12;m++)
      {   cout<<(m>1?xq[m]:"正")<<"月"
              <<(BIG(m)?"大":"小")<<"     ";
          if(++counter%4==0)cout<<"\n\n    ";
          if(p->run!=m)continue;
          cout<<"閏"<<xq[m]<<"月"
              <<(BIG(0)?"大":"小")<<"   ";
          if(++counter%4==0)cout<<"\n\n    ";
      }   getch();goto Menu;
   }
   else if(cho=='0')system("cls");
   return 0;