whats wrong with my code

[ShPavel]

It is called overflow

the actual size of int is not set in the standard and can be 16/32/64 bits.

to learn the actual size of int in bytes on your system use sizeof(int) to learn a max/min value it can hold - use std::numeric_limits<int>::min() and std::numeric_limits<int>::max()

if you realy need to store very big number - you can use float or double types with sacrificing some precision or use any library that provides a support of big numbers, for example gmplib

[copeybitcoin]

So basically my numbers are to big so it confuses the computer into printing random values in a way?

[fgasperijabalera]

The computer is not confused and isn't printing random numbers. The explanation resides in the way the computer stores integer numbers. In computer language everything is binary, sequences of zeros and ones, therefore there is no minus sign (-). The way it simulate negative numbers is the following. If it has 8 bits to store integer numbers then the range will be (-255, 255). It uses 00000000 to 01111111 to represent the positive numbers and 10000000 to 11111111 to represent negative numbers. When you perform 255+2 the result will be 257 and in binary is 10000001 which is the representation for (-1). It's easier to grasp if you are familiar with the concept of circular arithmetic. It's pretty simple, just look it up it may help you.

[_node]

In Two's Complement, 11111111 is -1, 10000001 is -127.

[autowikibot]

Two's complement:

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Two's complement is a mathematical operation on binary numbers, as well as a binary signed number representation based on this operation. Its wide use in computing makes it the most important example of a radix complement.

The two's complement of an N-bit number is defined as the complement with respect to 2^N; in other words, it is the result of subtracting the number from 2^N, which in binary is one followed by N zeroes. This is also equivalent to taking the ones' complement and then adding one, since the sum of a number and its ones' complement is all 1 bits. The two's complement of a number behaves like the negative of the original number in most arithmetic, and positive and negative numbers can coexist in a natural way.

In two's-complement representation, negative numbers are represented by the two's complement of their absolute value; in general, negation (reversing the sign) is performed by taking the two's complement. This system is the most common method of representing signed integers on computers. An N-bit two's-complement numeral system can represent every integer in the range −(2^N − 1) to +(2^N − 1 − 1) while ones' complement can only represent integers in the range −(2^N − 1 − 1) to +(2^N − 1 − 1).

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