Write a program which find the occurrence of substring in string ?

package test;

public class substring {

public static void main(String[] args) {
// TODO Auto-generated method stub
String str = "helloslkhellodjladfjhello";
    String findStr = "hello";
    int lastIndex = 0;
    int count = 0;

    while (lastIndex != -1) {

   
    System.out.println("first "+lastIndex);
    if (lastIndex != -1) {
    count++;
    lastIndex += findStr.length();
   
    }
    }
    System.out.println("number of substring"+count);

}

}

Write a program to closest prime number to any input number ?

package test;
import java.util.*;

public class closestprime {
public static boolean isprime(int a)
{int c=0;
for(int i=2;i<a/2;i++)
{
if(a%i==0)
{
c=1;
}
}

if(c==1)
         return false;
else
return true;


}

public static void main(String[] arg)
{
Scanner sc=new Scanner(System.in);
int a=sc.nextInt();
int i;
int n,n1,d,d1;
for(i=a+1;;i++)
{
if(isprime(i))
{    n=i;
    d=i-a;

break;
}
}
for(i=a-1;;i--)
{
if(isprime(i))
{    d1=a-i;
n1=i;

break;
}
}
if(d>d1)
System.out.println("closest prime no.: "+n1);
else if(d1>d)
System.out.println("closest prime no.: "+n);
else
System.out.println("closest prime no.: "+n+" "+n1);
}

}

Link List in Java

package test;
import java.util.*;

public class linklist<s> {
public node<s> head=null;

public void add()
{Scanner sc=new Scanner(System.in);
s a=(s) sc.nextLine();
head=new node<s>(a,head);
}
public void insert(int n,s b)
{node<s> temp=head;

for(int i=0;i<n;i++)
{
temp=temp.next;
}
temp.next=new node<s>(b,temp.next);

}
public void show()
{node<s> temp = head;
while(temp!=null)
{
System.out.println(temp.data);
temp=temp.next;

}
}
public class node<s>
{
s data;
node<s> next;
node(s a,node next)
{
this.data=(s) a;
this.next=next;
}
}
public static void main(String[] arg)
{

linklist<String> l=new linklist<String>();
for(int i=0;i<3;i++)
{
 l.add();
}

l.insert(2,"d");

l.show();
}


}

Anagram in java

package test;
import java.util.*;
public class anagram {
public static  String isanagram(String s,String s1)
{int x=s.length();
int y=s1.length();
if(x!=y)
return "not";
char a[]=s.toCharArray();
char b[]=s1.toCharArray();
Arrays.sort(a);
Arrays.sort(b);
if(Arrays.equals(a, b))
return "anagram";
else
return "not";
}
public static void main(String[] arg)
{
String s,s1;
Scanner sc=new Scanner(System.in);
s=sc.nextLine();
s1=sc.nextLine();
System.out.print(isanagram(s,s1));
}
}

Permutaion in java

package test;
import java.util.*;

public class permutation {
 public static void main(String args[]) {
   permuteString("", "ab");
 }

 public static void permuteString(String beginningString, String endingString) {
   if (endingString.length() <= 1)
    {
     System.out.println("print->"+beginningString + endingString+""+endingString.length());}
   else
   {  for (int i = 0; i < endingString.length(); i++) {
       try {
         String newString = endingString.substring(0, i) + endingString.substring(i + 1);
       
       
         permuteString(beginningString + endingString.charAt(i), newString);
       } catch (StringIndexOutOfBoundsException exception) {
         exception.printStackTrace();
       }
     }
 }
}
}

Palindrome of String in Java

import java.util.*;

public class palindrome {
public static void main(String[] args)
{
Scanner sc=new Scanner(System.in);
String a=sc.nextLine();
String x;
StringBuilder c=new StringBuilder();
c.append(a);
c=c.reverse();
String d=c.toString();

if(a.equals(d))
{
System.out.println("palindrom");
}
else
{
System.out.println("not");
}
}

}

Reverse Of Sentence in java

public class Sentence{

public static void main(String[] args) {
String a="i am kishan kumar";
String c=" ";
int j=0;
String[] b;
b=a.split(c);
for(int i=0;i<b.length;i++)
{
System.out.println(b[i]);
j++;
}

int k=j-1;
             for(int i=k;i>=0;i--)
          {
System.out.print(b[i]+" ");

             }
}

}