Title: Modulo for huge numbers
Question: how to calc 1882882323243435345 mod 29
Answer:
It is possible to calculate the result of a modulo operation
digit by digit:
function StringModulo(const s:string; modarg:Integer):Integer;
var
i : Integer;
begin
Result := 0;
for i := 1 to length(s) do
begin
// security check
if not (s[i] in ['0'..'9']) then
raise Exception.CreateFmt('StringModulo(%s, %d)'#13'Invalid Number !',
[s, modarg]);
Result := Result * 10 + ord(s[i])-Ord('0');
Result := Result mod modarg;
end;
end;
// Test cases to prove the function works properly
// 85391 mod 7 = 5
// 166199371 mod 13 = 0