Pascal - sum of digits in binary/hexadecimal

[tawi]

Homework Statement

Read two integers. First one tells you the type of your numeral system (binary, decimal, hexadecimal) the second one will be your number in decimal. Using functions or procedures I need to convert the number into the required system and then count the sum of its digits in that system. For example you are given the integers: 16, 17.
You convert the number 17 into hexadecimal, that is 11 and then you add up its digits and write the result. So your output in this case is 2.

Homework Equations

I´ve written two functions. One to convert the number and second to make the sum. The problem is that the first function output is a string whereas the second is an integer. That means I need to come up with a solution to convert the numbers without using string at all. And I have no idea at all how to do that.

The Attempt at a Solution

Here is what I´ve got so far. The first function needs to be replaced with something else.

program  abcd;
var  n,x,system: integer;

function convert(sys:byte;Nr:longint):string;

const Letters:string='0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ';

var temp:string;
  modulo:longint;

begin
  if sys>length(Letters) then
  writeln('system too big');

  temp:='';
  if Nr=0 then
  convert:='0'

  else begin

  modulo:= Nr;
  while modulo > sys - 1 do begin
  temp:=Letters[1+modulo mod sys]+temp;
  modulo:=modulo div sys  ;

  end;
  end;
  convert:=Letters[1+modulo]+temp;
  end;

function digitSum(number: longint): integer;  

var digit, torso, sumt: integer; 
begin
  sum := 0;
  torso := number;
  repeat
  digit := torso mod 10;
  sum := sum+ digit;
  torso := torso div 10;
  until torso = 0;
  digitSum := soucet;
end;

begin

  writeln(digitSum(?));

end.

 

[Mark44]

Homework Statement

Read two integers. First one tells you the type of your numeral system (binary, decimal, hexadecimal) the second one will be your number in decimal. Using functions or procedures I need to convert the number into the required system and then count the sum of its digits in that system. For example you are given the integers: 16, 17.
You convert the number 17 into hexadecimal, that is 11 and then you add up its digits and write the result. So your output in this case is 2.

Is the base limited to binary, decimal, or hex, or can it be some other base?

Also, what's the largest possible number your program should be able to convert? One parameter of your convert() function is type longint, which has a max. value of
2147483647.

Homework Equations

I´ve written two functions. One to convert the number and second to make the sum. The problem is that the first function output is a string whereas the second is an integer. That means I need to come up with a solution to convert the numbers without using string at all. And I have no idea at all how to do that.

The Attempt at a Solution

Here is what I´ve got so far. The first function needs to be replaced with something else.

Indenting your code would make it easier to follow the structure to be able to understand what you're doing.

program  abcd;
var  n,x,system: integer;

function convert(sys:byte;Nr:longint):string;

const Letters:string='0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ';

var temp:string;
  modulo:longint;

begin
  if sys>length(Letters) then
  writeln('system too big');

  temp:='';
  if Nr=0 then
  convert:='0'

  else begin

  modulo:= Nr;
  while modulo > sys - 1 do begin
  temp:=Letters[1+modulo mod sys]+temp;
  modulo:=modulo div sys  ;

  end;
  end;
  convert:=Letters[1+modulo]+temp;
  end;

function digitSum(number: longint): integer; 

var digit, torso, sumt: integer;
begin
  sum := 0;
  torso := number;
  repeat
  digit := torso mod 10;
  sum := sum+ digit;
  torso := torso div 10;
  until torso = 0;
  digitSum := soucet;
end;

begin

  writeln(digitSum(?));

end.

Here is your convert function, with indentation added by me.

function convert(sys:byte;Nr:longint):string;

const Letters:string='0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ';

var temp:string;
  modulo:longint;

begin
  if sys>length(Letters) then
     writeln('system too big');

     temp:='';
     if Nr=0 then
         convert:='0'
     else begin
        modulo:= Nr;
        while modulo > sys - 1 do begin
           temp:=Letters[1+modulo mod sys]+temp;
           modulo:=modulo div sys  ;
        end;
     end;
     convert:=Letters[1+modulo]+temp;
  end;

You are missing an end statement. Indenting your code properly would make it easier to catch errors like this.

 

[NascentOxygen]

The problem is that the first function output is a string whereas the second is an integer. That means I need to come up with a solution to convert the numbers without using string at all.

Does your Pascal have string functions that you are allowed to use, including convert integer to string and string to integer?

htîtp://www.baskent.edu.tr/~tkaracay/etudio/ders/prg/pascal/PasHTM1/pas/pasl1007.html