Why does rand() + rand() produce negative numbers?

Question

I observed that rand() library function when it is called just once within a loop, it almost always produces positive numbers.

for (i = 0; i <         


        

Answer 1

rand() is defined to return an integer between 0 and RAND_MAX.

rand() + rand()

could overflow. What you observe is likely a result of undefined behaviour caused by integer overflow.