dec3 编解码源程序 .从别的网站下载后稍作修改，增加了入口main函数。能编译通过，但是还不能运行。库函数都可以用-encrpt source code, dec3, include dec3.c, dec3.h, two files, download from other sites and do small modifications

使用C语言实现的三个密钥的三重DES算法。-The use of C language implementation of the three-key triple DES algorithm.

Triple DES is the common name for the Triple Data Encryption Algorithm (TDEA or Triple DEA) symmetric-key block cipher, which applies the Data Encryption Standard (DES) cipher algorithm three times to each data block.