Q1_3.java

import java.util.HashMap;
import java.util.Arrays;
public class Q1_3{
  public static void main(String args[]){
    String str1= "123gefrfd";
    String str2= "231gerfdd";
    System.out.println(isPermutation1(str1, str2));
  }
  public static boolean isPermutation2(String str1, String str2){
    if(str1.length()!=str2.length())
      return false;
    char[] array1 = str1.toCharArray();
    char[] array2 = str2.toCharArray();
    Arrays.sort(array1);
    Arrays.sort(array2);
    for( int i = 0; i < array1.length; i++){
      if(array1[i] != array2[i])
        return false;
    }
    return true;
  }
  public static boolean isPermutation1(String str1, String str2){
    if(str1.length()!=str2.length())
      return false;
    
    HashMap<Character,Integer> map = new HashMap<Character,Integer>();
    
    for(int i =0; i <str1.length();i++){
      Character c = str1.charAt(i);
      if(map.containsKey(c))
        map.put(c, map.get(c)+1);
      else map.put(c,1); 
      
    }
    for(int i = 0; i<str2.length(); i++){
      Character c = str2.charAt(i);
      if(map.containsKey(c)){
        if(map.get(c)>0)
          map.put(c, map.get(c)-1);
        else return false;
      }
      else return false; 
      
    }
    return true;
    
  }
}