代码部分
import java.util.Scanner;
class Encryption{
public void Encryption() {
char l;
System.out.println(“请输入要加密的明文”);
Scanner input = new Scanner(System.in);
String str1 = input.nextLine();
System.out.println(“请输入要加密的**”);
int k = input.nextInt();
System.out.print("加密后的明文为: ");
for(int i = 0 ; i < str1.length() ; i ++) {
int n = (int)(str1.charAt(i));
if(n > 96 && n < 123) {
n = (n - 97 + k) % 26;
l = (char)(n + 97);
System.out.print(l);
}
}
}
}
class Decrypt{
public void Decrypt() {
char l ;
System.out.println(“请输入需要解密的密文”);
Scanner input = new Scanner(System.in);
String str3 = input.nextLine();
System.out.println(“请输入解密的**”);
int k = input.nextInt();
System.out.println(“解密的明文是： “);
for(int i = 0 ; i < str3.length() ; i ++) {
int n = (int)(str3.charAt(i));
if(n > 96 && n < 123) {
n = (n - 97 - k) % 26;
if(n == -1)
n = 25;
l = (char)(n + 97);
System.out.print(l);
}
}
}
}
public class internetservice{
public static void main(String[] args) {
while(true) {
System.out.println(”\n选择功能”);
System.out.println(“1. 加密功能”);
System.out.println(“2. 解密功能”);
Scanner input = new Scanner(System.in);
int c = input.nextInt();
switch© {
case 1 :{
Encryption encryption = new Encryption();
encryption.Encryption();
break;
}
case 2 : {
Decrypt decrypt = new Decrypt();
decrypt.Decrypt();
break;
}
}
}
}
}