c++弗吉尼亚算法及单表替换加密

#include <iostream> #include <fstream> using namespace std; class Coding { public: char* Deciphering(char* input,char* key); char* Encryption(char* input,char* key); int Len(char* str); }; int Coding::Len(char* str) { return strlen(str); } char* Coding::Encryption(char* input,char* key) { int lenk=Len(key); int temp=Len(input); for(int i=0;i<temp;i++) { if(input[i]<91&&64<input[i]) input[i]+=32; else if(input[i]<123&&96<input[i]) input[i]-=32; input[i]+=key[i%lenk]; } return input; } char* Coding::Deciphering(char* input,char* key) { int lenk=Len(key); int temp=Len(input); for(int i=0;i<temp;i++) { input[i]-=key[i%lenk]; if(input[i]<91&&input[i]>64) input[i]+=32; else if(input[i]<123&&input[i]>96) input[i]-=32; } return input; } void main(int argc,char*argv[]) { if(argc!=5) { cout<<endl<<"请按以下格式输入：Cryptography_1 -e/-d key inputfile outputfile "<<endl; exit(0); } Coding obj; fstream file(argv[3],ios::out|ios::in|ios::binary, _SH_DENYRW); fstream file2(argv[4],ios::out|ios::in|ios::trunc|ios::binary, _SH_DENYRW); char* key=argv[2]; char* select=argv[1]; int length=0; file.seekg(0,ios::end); length=file.tellg(); char* data=new char[length+1]; file.seekg(0,ios::beg); file.getline(data,length+1); //cout<<obj.Len(data)<<data<<endl; char* output="指令无法识别！！无法完成加解密任务！！"; //cout<<argv[1]<<endl; if(select[1]=='e') output=obj.Encryption(data,key); else if(select[1]=='d') output=obj.Deciphering(data,key); file2.write(output,obj.Len(output)); }