1. A random number generator (RNG), comprising: a memory bit array having a plurality of bits, wherein each bit is configured to present an initial logic state when the memory bit array is powered on; and a first folding circuit coupled to the memory bit array, wherein the first folding circuit is configured to: read initial logic states of a first bit and a second bit of the memory bit array, perform a first logic function on the initial logic state of the first bit, and perform a second logic function on the initial logic state of the second bit to contaminate the initial logic state of the second bit so as to provide an altered initial logic state of the second bit.