Sabiranje

program Sabiranje
{ Sabiranje velikih brojeva }

var s1, s2, s3 : string;
    l1, l2 : integer;

procedure dopuni(var s : string, k : integer);
var i : integer;
begin
    for i := 1 to k do s := '0' + s;
end;

procedure saberi(var s1, s2, s3 : string);
var c, c1, prenos, i : integer;
    s : string;
begin
    s3 := '';
    prenos := 0;
    i := length(s1);
    while (i > 0) do begin
        c := ord(s1[i]) + ord(s2[i]) - 2 * ord('0') + prenos;
        c1 := c mod 10;
        prenos = c div 10;
        str(c1, s);
        s3 := s + s3;
        i := i - 1;
    end;
end;

procedure skrati(var s : string)
var i : integer;
begin
    i := 1;
    while(s[i] = '0' do begin
        s[i] := ' ';
        i := i + 1;
    end;
end;

begin
    write('Prvi broj: '); readln(s1); l1 := length(s1);
    write('Drugi broj: '); readln(s2); l2 := length(s2);
    if l1 < l2 then dopuni(s1, l2 - l1) else dopuni(s2, l1 - l2);
    saberi(s1, s2, s3);
    skrati(s1); skrati(s2); skrati(s3);
    writeln(s1, ' + ', s2, ' = ', s3);
    readln;
end.