Programming :: Dividing A String Into Substrings With Three Elements In C++

im trying to receive a string from user, then divide it into groups of strings with 3 elements only. meaning if input is:

12345 it should give 123 and 45
123456 it should give 123 and 456
1234567 it should give 123 and 456 and 7

anyway what happens based on my code is that it works fine with first two (when it has groups of 3 elements and 2 element, and also when it has groups of all 3 elements) but for the last case (when makes groups of 3 elements and 1 group of 1 element) it shouws as "123 456 7 D"!! meaning it adds one extra character to the last element out of no where!

here is my code:

Code:
#include <iostream>
#include <conio>
struct array
{

[Code]....