public classcryptosystem { public static void main(String []args) {charoutput[]=

Question

public classcryptosystem
{
public static void main(String []args)
{charoutput[]={'A','B','C','D','E','F','G','H','I','J','K','L','M',
                'N','O','P','Q','R','S','T','U','V','W','X','Y','Z'};
char [] encr=new char[26];
char []outword=new char [20];
String key,inword;
char c;
boolean good=true,wrap;
int i,j,len,start,stop,n,encrptr,beg,end,k;
Random number = new Random();
Scanner in=new Scanner(System.in);
do
{
System.out.print("Enter a key ");
good=true;
key=in.next();
len=key.length();
if(len<5||len>26)
     {good=false;
      len=0;
      }
for(i=0;i<len-1;i++)
    for(j=i+1;j<len;j++)
        if(key.charAt(i)==key.charAt(j))
             good =false;
if(!good)
    System.out.println("invalid key ");
}while(!good);
n=number.nextInt(25)+1;
//System.out.print("Enter n");               //for testing
//n=in.nextInt();                        //for testing
start=n-1;
stop=(start+len-1)%26;
//System.out.println("stop "+stop+" start"+start);       //for testing
if(stop<start)
     wrap=true;
else
     wrap=false;
encrptr=0;
if(!wrap)
    for(i=0;i<26;i++)
      {//System.out.println("i="+i);
         if(encrptr<start||encrptr>stop)
            { if(!inkey(output[i],key,len))
                  { encr[encrptr++]=output[i];
                    // System.out.println("1 "+encr[encrptr-1]+" "+encrptr);
                   }
           }
           else
             {for(j=0;j<len;j++)
                 {encr[encrptr++]=key.charAt(j);
                //    System.out.println("2 "+encr[encrptr-1]+""+encrptr);
                 }
                i--;
                }
           }
else
     for(i=0;i<26+26-start;i++)
      {//System.out.println("i="+i+"Encrypt stop start "+encrptr+" "+stop+""+start);
         if(encrptr>stop&&encrptr<start)
            { if(!inkey(output[i],key,len))
                  { encr[encrptr++]=output[i];
                    //    System.out.println("3 "+encr[encrptr-1]+""+encrptr);
                   }
           }
           else
             { //System.out.println("here "+i);
             if(i!=0)
                 { beg=0;
                     end=26-n+1;

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