Reverse_Each_Word

package interview;

public class Reverse_Each_Word
{

public static void main(String[] args)
{
String s1 = "java programming uses JVM";
String[] s2 = s1.split(" ");  //[java , programming]
String rev = "";
for(int i = 0;i<s2.length;i++)
{
  String s = s2[i]; //java
 
for(int j =s.length()-1; j>=0 ;j--)
{
rev = rev + s.charAt(j);
}
rev= rev +" ";
}
System.out.println("Original: "+s1);
System.out.println("Reversed: "+rev);


}
}

RemoveSpace

package interview;
//Remove white space
public class RemoveSpace {

public static void main(String[] args)
{
//*******************************************  
  String s1 = "remove white space";
  String s2 = s1.replaceAll("\\s","");
  String s4 = s1.replaceAll("\\s","~");
  System.out.println(s2);
  System.out.println(s4);
//*******************************************
  String s3 = "remove white space";
  char[] ch = s3.toCharArray();
  StringBuffer sb = new StringBuffer();
  for(char c : ch)
  {
  if (c!=' ')
  {
  sb = sb.append(c);
  }
  }
  System.out.println(sb);                                                                                                            
}

}

ReverseEachSring_StringBuffer

package interview;

public class ReverseEachSring_StringBuffer {

public static void main(String[] args)
{

String s1 = "java programming uses JVM";
String[] s2 = s1.split(" ");  //[java , programming]
StringBuffer buffer =new StringBuffer();
for(int i = 0;i<s2.length;i++)
{      
for(int j =s2[i].length()-1; j>=0 ;j--)
{

buffer = buffer.append(s2[i].charAt(j));
}
buffer = buffer.append(" ");

}
System.out.println("Original: "+s1);
System.out.println("Reversed: "+buffer);


}



}

ReverseEachString_CharArray

package interview;

public class ReverseEachString_CharArray
{
public static void main(String[] args)
{
String s1 = "java programming uses JVM";
String rev ="";
String[] s2 = s1.split(" ");
System.out.println(s1);
for(String s : s2)
{

char[] ch = s.toCharArray();

for(int i =ch.length-1 ;i>=0;i--)
{
System.out.print(ch[i]);
}

System.out.print(" ");
}

}

}

Reverse String Custom

package interview;


public class ReverseString_Custom {

public static void main(String[] args)
{
 
  String orig = "This is a Tree";
  String rev = "";
  int len = orig.length();
  for(int i = len-1;i>=0;i--)
  {
  rev = rev + orig.charAt(i);
  }
  System.out.println(orig);
  System.out.println(rev);
}

}

Reverse String

package interview;

import java.util.Scanner;

public class ReverseString {

public static void main(String[] args)
{
String original;
String rev;

System.out.println("Enter a String");
Scanner kb = new Scanner(System.in);
original = kb.nextLine();

 
  //***********Using InBuild methods
 
  StringBuffer sb = new StringBuffer(original);
  rev = sb.reverse().toString();
  System.out.println(rev);
 

}

}

Find No. of Words: No. of characters: List to duplicate Words from text File

package test;

import java.io.BufferedReader;
import java.io.FileNotFoundException;
import java.io.FileReader;
import java.io.IOException;
import java.util.Arrays;
import java.util.HashMap;
import java.util.Map;

/*
No. of Words:
No. of characters:
List to duplicate Words:
D:\work\Java Work Space\files\amit.txt
*/
public class Count_Duplicate_Words_From_File
{
public static void main(String[] args) throws IOException, FileNotFoundException
{
  BufferedReader br = new BufferedReader(new FileReader("D:\\work\\Java Work Space\\files\\amit.txt"));
  StringBuffer sb = new StringBuffer();
  String s = br.readLine();
  while(s!= null)
  {
  //sb = sb.append(s); //----->White ko hatna hetu
  sb = sb.append(s.trim());
  sb = sb.append(" ");
  s = br.readLine();
  }
  br.close();
  String[] words = sb.toString().split(" ");
  wordCount(words);
  charCount(words);
  DupWords(words);
 
}

private static void DupWords(String[] words)
{
  Map <String,Integer> map = new HashMap<>();
  for(String s : words)
  {
  if(!map.containsKey(s))
  {
  map.put(s, 1);
  }
  else
  {
  map.put(s, map.get(s)+1);
  }
  }
  System.out.println("List to duplicate Words:");
  for(Map.Entry<String,Integer> entry : map.entrySet())
  {
  if(entry.getValue()>1)
  System.out.println(entry.getKey()+" : "+entry.getValue());
  }

}

private static void charCount(String[] words)
{
char[] ch;
int count = -1;
  for (String s : words)
  {
for(int i = 0;i<s.length();i++)
{
count++;
}
count++;
  }
  System.out.println("No. of characters: "+count);

}

private static void wordCount(String[] words)
{
  System.out.println(Arrays.toString(words));
  System.out.println("No of Words: "+words.length);

}
}