java program to check whether a string is made up of unique characters or not ..

/*java program to check whether a string is made up of unique characters or not ..*/

       

import java.io.*;
public class P11 {
 public static void main(String args[]) {
  boolean[] ch = new boolean[256];

  String name = "gaurv##";

  for (int i = 0, val; i < name.length(); i++) {
   val = name.charAt(i);
   if (ch[val]) {
    System.out.println("string is not unique");
    return;
   } else {
    ch[val] = true;
   }
  }
  System.out.println("string is unique");
 }
}

       
 

Check whether two strings are anagrams or not using java....

/*java program to check whether two strings are anagrams */

       

import java.io.*;
public class P14 {
 public static void main(String args[]) {
  char chr[] = {
   'g',
   'a',
   'u',
   'r',
   'a',
   'v',
   's'
  };
  char chr1[] = {
   'v',
   'a',
   'g',
   'a',
   'u',
   'r',
   'k'
  };
  int[] boo = new int[256];
  if (chr.length != chr1.length) {
   System.out.println("strings are not anagrams");
   return;
  }

  for (int i = 0, val; i < chr.length; i++) {
   val = chr[i];
   boo[val] = boo[val] + 1;
  }


  try {
   for (int k = 0, val1; k < chr1.length; k++) {
    val1 = chr1[k];
    if (boo[val1] != 0) {
     boo[val1] = boo[val1] - 1;
    } else {
     System.out.println("strings are not anagrams");
     return;
    }
   }
  } catch (Exception e) {
   System.out.println("error found");
  }
  System.out.println("strings are anagrams ");
 }
}

       
 

java program to replace the spaces in a string by '%20'.

Here is the code ....

       

public class P15 {
 public static void main(String args[]) {
  String name = "gaurav kumar yadav";
  int val = 0;
  for (int i = 0; i < name.length(); i++)
   if (name.charAt(i) == ' ') val = val + 1;

  char[] chr = new char[name.length() + 2 * val];
  for (int l = 0, s = 0; l < name.length(); l++) {
   if (name.charAt(l) != ' ') {
    chr[s] = name.charAt(l);
    s++;
   } else {
    chr[s] = '%';
    chr[++s] = '2';
    chr[++s] = '0';
    s++;
   }

  }
  String name1 = new String(chr);
  System.out.println(name1);
 }
}