本次我们完成一个简单的对字母加密程序。首先对字母进行编号，小写字母a至z编号为1至26，大写字母A至Z分别编号27至52，这样每个字母都有唯一的一个序号，在发送内容时，我们以函数F(X)=X*X+X+1对发送字母的序号进行计算，就会获取个新的序号，对该序号再进行对52取余，该序号即为加密后的要发送字母的序号，这样就能达到加密的作用。-This time we complete a simple encryption program on the letter. First letter number and the lowercase letters a to z No. 1-26, the uppercase letters A to Z are numbered 27-52, so that each letter has a unique serial number when sending content, the function of the F (X ) = X* X+X+1 send letters serial number calculation, it will obtain a new serial number, the serial number and then the remainder of 52, the serial number is the serial number you want to send encrypted letters, so that we can achieve encryption role.