Merge pull request #112 from Sayantan1024/main

Added CeaserCipher, Goldbach, PrimeAdam java programs

Author: Ritikraja07

CeaserCipher.java

@@ -0,0 +1,51 @@
+import java.util.*;
+class CaeserCipher
+{
+    String s; //declaration
+    public CaeserCipher() //default constructor to initialise s
+    {
+        s="";
+    }
+    void input() //input text
+    {
+        Scanner sc=new Scanner(System.in);
+        System.out.println("enter text");
+        s=sc.nextLine();
+    }
+    void encrpyt()
+    {
+        int L; //declaration
+        char ch;
+        String s1="";
+        L=s.length();
+        if(L>3 && L<100)
+          {
+              for(int i=0;i<L;i++)
+                 {
+                     ch=s.charAt(i); //character extraction
+                     if(ch>='A' && ch<='M' || ch>='a' && ch<='m')
+                        s1=s1+(char)(ch+13);
+                        else 
+                          if(ch>='N' && ch<='Z' || ch>='n' && ch<='z')
+                              s1=s1+(char)(ch-13);
+                           else 
+                              s1=s1+ch;
+                        }
+              System.out.println("Encrypted text="+s1); //printing
+            }
+            else
+              System.out.print("INVALID LENGTH");
+    }
+    public static void main()
+    {
+        CaeserCipher ob=new CaeserCipher(); //creating object ob
+        ob.input(); //calling function
+        ob.encrpyt(); //calling function
+    }
+}    
+                     
+        
+       
+    
+    
+    

Goldbach.java

@@ -0,0 +1,54 @@
+import java.util.*;
+class Goldbach
+{
+    int N; //declaration
+    public Goldbach() //default constructor to initialise N
+    {
+        N=0;
+    }
+    void input() //to input N
+    {
+        Scanner sc=new Scanner(System.in);
+        System.out.println("Enter a number");
+        N=sc.nextInt();
+    }    
+    int prime(int n) //to check for prime
+    {
+        int c=0;
+        for(int i=1;i<=n;i++)
+           {
+               if(n%i==0)
+                  c++;
+            }        
+        return c;
+    }    
+    void sum()
+    {
+        if(N%2==0) 
+          {
+              if(N>9 && N<50)
+                {
+                   for(int i=3;i<=N/2;i++)
+                     {
+                         for(int j=3;j<=N;j++)
+                            {
+                                if(i+j==N && prime(i)==2 && prime(j)==2)
+                                  {
+                                      System.out.println("Prime pairs are="+i+" "+j); //printing the odd prime pairs
+                                    }
+                                }
+                            }
+                        }            
+               else
+                  System.out.print("Invalid input,Number out of range");
+                }
+            else
+               System.out.print("Invalid input,number is Odd");
+    }
+    public static void main()
+    {
+        Goldbach ob=new Goldbach(); //creating object
+        ob.input(); //calling
+        ob.sum(); //calling
+    }
+} 

PrimeAdam.java

@@ -0,0 +1,65 @@
+import java.util.*;
+class PrimeAdam
+{
+    int m,n; //declaration
+    public PrimeAdam()
+    {
+        m=n=0;
+    }
+    void input() //input lower and upper range
+    {
+        Scanner sc=new Scanner(System.in);
+        System.out.println("Enter m and n");
+        m=sc.nextInt();
+        n=sc.nextInt();
+    }
+    int prime(int no) //check for prime 
+    {
+        int c=0; //declaration
+        for(int i=1;i<=no;i++)
+           {
+               if(no%i==0)
+                 c++;
+                }
+        return c;
+    }
+    int adam(int no) //check for adam
+    {
+        int s=0,p=1,s1=0; //declaration
+        while(no>0)
+        {
+            s=s*10+(no%10);
+            no=no/10;
+        }
+        p=s*s;
+        while(p>0)
+        {
+            s1=s1*10+(p%10);
+            p=p/10;
+        }
+        return s1;        
+    }
+    void print() //printing prime-adam numbers between m and n
+    {
+        int c=0; //declaration
+        for(int i=m;i<=n;i++)
+           {
+               if((prime(i)==2) && ((adam(i))==(i*i)))
+                  {
+                      System.out.print(i+" ");
+                      c++;
+                    }
+                }
+        System.out.println();
+        System.out.print("FREQUENCY OF PRIME-ADAM INTEGERS IS="+c);
+    }
+    public static void main()
+    {
+        PrimeAdam ob=new PrimeAdam(); //creating object ob
+        ob.input(); //calling function
+        ob.print(); //calling function
+    }
+}
+    
+       
+