日历

日历.png

program calendar(input, output);
var
    year, month : integer;
    valid : boolean;

    function isLeapYear(year : Integer) : boolean;
    var
        ans : boolean;
    begin
        ans := (year mod 4 = 0) and (year mod 100 <> 0);
        ans := (year mod 400 = 0) or ans;  
        isLeapYear := ans;
    end;

    function daysInMonth(month, year : integer) : integer;
    begin
        if isLeapYear(year) and (month = 2) 
            then daysInMonth := 29
        else if month = 1 
            then daysInMonth := 31
        else if month = 2   
            then daysInMonth := 28
        else if month = 3 
            then daysInMonth := 31
        else if month = 4 
            then daysInMonth := 30
        else if month = 5 
            then daysInMonth := 31
        else if month = 6 
            then daysInMonth := 30
        else if month = 7 
            then daysInMonth := 31
        else if month = 8 
            then daysInMonth := 31
        else if month = 9 
            then daysInMonth := 30
        else if month = 10 
            then daysInMonth := 31
        else if month = 11 
            then daysInMonth := 30
        else if month = 12 
            then daysInMonth := 31
    end;

    function dayOfWeek(d, m, y : integer) : integer;

        function aux(m : integer) : integer;
        begin
            if m = 0 then aux := 0
            else if m = 1 then aux := 3
            else if m = 2 then aux := 2
            else if m = 3 then aux := 5
            else if m = 4 then aux := 0
            else if m = 5 then aux := 3
            else if m = 6 then aux := 5
            else if m = 7 then aux := 1
            else if m = 8 then aux := 4
            else if m = 9 then aux := 6
            else if m = 10 then aux := 2
            else if m = 11 then aux := 4            
        end;

    begin
        if m < 3 then y := y - 1;
        dayOfWeek := (y + y div 4 - y div 100 + y div 400 + aux(m - 1) + d) mod 7
    end;

    procedure printCalendar();
    const
        ALIGN = 14;
    var
        i, j : integer;
    begin

        i := 1;
        j := 1;
        
        if month = 1 then writeln('January' : ALIGN)
        else if month = 2 then writeln('February' : ALIGN)
        else if month = 3 then writeln('March' : ALIGN)
        else if month = 4 then writeln('April' : ALIGN)
        else if month = 5 then writeln('May' : ALIGN)
        else if month = 6 then writeln('June' : ALIGN)
        else if month = 7 then writeln('July' : ALIGN)
        else if month = 8 then writeln('August' : ALIGN)
        else if month = 9 then writeln('September' : ALIGN)
        else if month = 10 then writeln('October' : ALIGN)
        else if month = 11 then writeln('November' : ALIGN)
        else if month = 12 then writeln('December' : ALIGN);

        writeln('Su Mo Tu We Th Fr Sa');

        while i <> dayOfWeek(1, month, year) do begin
            write('    ');
            i := succ(i);
            j := succ(j);
        end;

        i := 1;
        while i <= daysInMonth(month, year) do begin
            write(i : 3); i := succ(i);
            
            j := succ(j);
            if j mod 7 = 0 then writeln();
        end;
        writeln();
    end;


begin
    valid := true;
    while valid do begin
        write('MONTH: '); read(month);
        write('YEAR: '); read(year);
        if (month in [1 .. 12]) then begin
            printCalendar();
            valid := false
        end
        else begin
            writeln('Invalid month, try again.');
            valid := true
        end     
    end;    
end.

温馨提示：不要复制粘贴，你需要的练习是：自己动手慢慢敲代码
一些有用的链接：
CP Pascal Editor下载链接
Free Pascal下载链接
那些初高中甚至小学就接触编程的人最后到了什么样的境界？
高中生如何学习编程？

2015年4月21日01:57:17 @kaikai