Hamming Distance

In information theory, the Hamming distance between two strings of equal length is the number of positions at which the corresponding symbols are different. In another way, it measures the minimum number of substitutions required to change one string into the other, or the minimum number of errors that could have transformed one string into the other.

The Hamming distance is named after Richard Hamming, who introduced it in his fundamental paper on Hamming codes Error detecting and error correcting codes in 1950.

It is used in telecommunication to count the number of flipped bits in a fixed-length binary word as an estimate of error, and therefore is sometimes called the signal distance. Hamming weight analysis of bits is used in several disciplines including information theory, coding theory, and cryptography.

For example , the binary representation of 9₁₀ is 1001₂ and 10₁₀ is 1010₂ therefore distance Hamming between them is 2 because you only need to switch the last two bits 1001₂ to turn in 1010₂.

Your task is , given two positive integers , calculate the Hamming distance between them.