โปรแกรมแปลงอุณหภูมิ

โปรแกรมแปลงอุณหภูมิ หัดทำ แนะนำด้วย
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program temp;
uses crt;
var temperature:real;
    i:integer;
    ans:char;
begin
repeat
    clrscr;
    writeln('***** Wellcome To Program Temperature Conversion *****');
    writeln('------------------------------------------------------');
    writeln('1.Convers Celsius To Fahrenheit,Reaumur,Kelvin');
    writeln('2.Convers Fahrenheit To Celsius,Reaumur,Kelvin');
    writeln('3.Convers Kelvin To Celsius,Reaumur,Fahrenheit');
    writeln('4.Convers Reaumur To Celsius,Fahrenheit,Kelvin');
    writeln;
    write('Plese Select Program = ');
    readln(i);
    case i of
1 : begin
    clrscr;
    writeln('Program Convers Celsius To Fahrenheit,Reaumur,Kelvin');
    writeln('--------------------------------------------------');
    write('Input Temperature((-273.15)-300) = ');readln(temperature);
    writeln('Temperature In Fahrenheit is = ',(9/5*temperature)+32:1:2);
    writeln('Temperature In Reaumur is = ',0.8*temperature:1:2);
    writeln('Temperature In Kelvin is = ',temperature+273.15:1:2);
    end;
2 : begin
    clrscr;
    writeln('Program Convers Fahrenheit To Celsius,Reaumur,Kelvin');
    writeln('----------------------------------------------------');
    write('Input Temperature((-459.67)-572) = ');readln(temperature);
    writeln('Temperature In Celsius is = ',5/9*(temperature-32):1:2);
    writeln('Temperature In Reaumur is = ',(temperature-32)*4/9:1:2);
    writeln('Temperature In Kelvin is = ',(temperature+459.67)*5/9:1:2);
    end;
3 : begin
    clrscr;
    writeln('Program Convers Kelvin To Celsius,Reaumur,Fahrenheit');
    writeln('----------------------------------------------------');
    write('Input Temperature(0-573.15) = ');readln(temperature);
    writeln('Temperature In Celsius is = ',temperature-273.15:1:2);
    writeln('Temperature In Reaumur is = ',(temperature-273.15)*4/5:1:2);
    writeln('Temperature In Fahrenheit is = ',temperature*9/5-459.67:1:2);
    end;
4 : begin
    clrscr;
    writeln('Program Convers Reaumur To Celsius,Fahrenheit,Kelvin');
    writeln('----------------------------------------------------');
    write('Input Temperature((-218.52)-240) = ');readln(temperature);
    writeln('Temperature In Celsius is = ',temperature*5/4:1:2);
    writeln('Temperature In Kelvin is = ',temperature*5/4+273.15:1:2);
    writeln('Temperature In Fahrenheit is = ',temperature*9/4+32:1:2);
    end;
    else
        begin
              clrscr;
              writeln('Your Unkwon Choice!!')
        end;
    end;
          writeln;
          write('Plese Any Key To continue(Enter)');
          readln;
    clrscr;
    Write('Do you want to continue (Y/N) = ');readln(ans);
    ans:=upcase(ans);
    until ans ='N';
    end.