SM4对称密码的加解密，适合初学者学习，很简便，使用环境是在VC上-SM4 symmetric cipher encryption and decryption, suitable for beginners to learn, very easy to use environment on VC

国密 sm2 sm3 sm4 加密算法 椭圆曲线算法 摘要算法 对称加解密(The symmetric encryption and decryption algorithm for the elliptic curve algorithm of the national dense SM2 SM3 SM4 encryption algorithm)