RSA加密解密 (输入数值)

 
//只是简单地实现了加密解密,并未实现 验证参数p,q互质,e与(p-1)(q-1)互质

import java.util.*;
 public class RSA{
     public static void main (String args[]){
         
             System.out.println("请依次输入p,q,e,字母数值 ");             
             Scanner scan=new Scanner (System .in);
             int p=scan.nextInt();
             int q=scan.nextInt();
             int e=scan.nextInt();
             int letter=scan.nextInt();
             
             int n=p*q;              
             int a=(p-1)*(q-1);             
             int d=0;
             
             do {
                 d++;             
             }while(((d*e)%a)!=(1%a));              
             
                     System .out.println("请选择操作");
                     System .out.println("1:加密 ");
                     System .out.println("2:解密 ");                      
                     int t=scan.nextInt();
                      
                     switch (t ){
                     case 1: 
                         int Me=1;
                         int i=0 ;                         
                         while( i<e){                             
                             Me=Me*letter;
                             Me=(Me%n);                          
                             i++;
                         }
                         System.out. print("明文:"+letter+"   公钥:<"+e+","+n+">   密文:" +Me);
                         break;                         
                         
                     case 2:                         
                         int Cd=1;
                         int j=0 ;                         
                         while( j<d){                             
                             Cd=Cd*letter;
                             Cd=Cd%n;    
                             j++; 
                         } 
                         System.out. print("密文:"+letter+"   私钥:<"+d+","+n+">   明文:" +Cd);
                         break;                               
                     }
            }

      
 }