数据结构实验-密码的原理与实现.docVIP

电气信息学院 实 验 项 目 密码的原理与实现 　 专 业 班 组 通信202班 　 实 验 时 间 2016.12.12 　 成 绩 评 定 　 评 阅 老 师 　 报告撰写人： 学号： 电气信息学院专业中心实验室 一、实验内容 利用Visual C++设计合理的凯撒密码，对一段英文段落进行加密处理。以每个人学号的最后两位为key。 英文段落如下： I am Wang Yanling,a student from Sichuan University.Now I major in telecommunication engineering.I am nineteen years old and my family live in Sichuan province.It is the second year of my colleage and I am fighting for my future.I also enjoy playing games,listening to some beautiful music and going out for a date with my friends.How wonderful it is. 二、算法流程图 三、详细设计 源程序： #includestdio.h #includestdlib.h#includeconio.hchar?encrypt(char?ch,int?n)/*加密函数，把字符向右循环移位n*/{while(ch=Ach=Z){return?(A+(ch-A+n)%26);}while(ch=ach=z){return?(a+(ch-a+n)%26);}return?ch;}void?menu()/*菜单，1.加密，2.解密，3.退出*/{printf(\n----------------------);printf(\n1.Encrypt?the?file);printf(\n2.Decrypt?the?file);printf(\n3.Quit\n);printf(------------------------\n);printf(Please?select?a?item:);return;}main(){int?i,n;char?ch0,ch1;FILE?*in,*out;char?infile[20],outfile[20];menu();ch0=getch();while(ch0!=3){??if(ch0==1)??{???printf(\nPlease?input?the?infile:);???scanf(%s,infile);/*输入需要加密的文件名*/???if((in=fopen(infile,r))==NULL)???{???printf(Can?not?open?the?infile!\n);???printf(Press?any?key?to?exit!\n);???getch();???exit(0);???}???printf(Please?input?the?key:);???scanf(%d,n);/*输入加密密码*/???printf(Please?input?the?outfile:);???scanf(%s,outfile);/*输入加密后文件的文件名*/???if((out=fopen(outfile,w))==NULL)???{???printf(Can?not?open?the?outfile!\n);???printf(Press?any?key?to?exit!\n);???fclose(in);???getch();???exit(0);???}???while(!feof(in))/*加密*/???{???fputc(encrypt(fgetc(in),n),out);???}???printf(\nEncrypt?is?over!\n);???fclose(in);???fclose(out);??}??if(ch0==2)??{??printf(\nPlease?input?the?infile:);??scanf(%s,infile);/*输入