MD5算法：MD5以512位分组来处理输入的信息，且每一分组又被划分为16个32位子分组，经过了一系列的处理后，算法的输出由四个32位分组组成，将这四个32位分组级联后将生成一个128位散列值-The MD5 algorithm: MD5 with 512 bit block to process input information, and each group was divided into 16 groups of 32 seats, after a series of processing, the output of the algorithm is composed of four 32 bit block, the four 32 bit grouped cascade will generate a hash value of 128