"int" is too small to store large numbers!
That's why you decided to implement your own data type, BigInt.
You need to implement 7 basic functions:
1. Constructor. It is initalized by a string representing a non-negative integer without leading zeroes (despite "0" itself).
2. Destructor.
3,4,5,6. ++x, x++, --x, x--, as in the C/C++ standard.
7: char* to_s(): returns a duplicate of the number in char*, e.g., "123".
UPDATE:
Note that you don't need to implement negative numbers. When the number is 0 and you have to decrement it, you can ignore the operation.
The first line contains an integer T, representing the number of testcases that follow.
For each testcase, a non-negative integer less than pow(10, 1023) is given in the first line.
An integer Q follows, representing the number of operations regarding the testcase.
Q lines follow, each in the form of "B++", "++B", "B--", or "--B", the effect of which is the same as specified in the C/C++ standard.
For each operation, print the result in one line, without leading zeroes.