Remove Character From String1 which are present in String2

You are given two strings, remove the characters from the first string which are present in the second string.

Algorithm: Let first input string be “test string” and the string which has characters to be removed from first string be “mask”
1: Initialize:
res_ind = 0 /* index to keep track of processing of each character in i/p string */
ip_ind = 0 /* index to keep track of processing of each character in the resultant string */

2: Construct count array from mask_str. Count array would be:
(We can use Boolean array here instead of int count array because we don’t need count, we need to know only if      character is present in mask string)
count['a'] = 1
count['k'] = 1
count['m'] = 1
count['s'] = 1

3: Process each character of the input string and if count of that character is 0 then only add the character to the resultant string.
str = “tet tringng” // ’s’ has been removed because ’s’ was present in mask_str but we we have got two extra characters “ng”
ip_ind = 11
res_ind = 9

4: Put a ‘′ at the end of the string if required.

Reference -

Java code sample is :

public class RemoveFirstFromSecond {
public static void main(String[] args) {
  String first = "this is a test";
  String second = "mask";
  boolean bit[] = new boolean[256]; //boolean are defaulted to false
  //Set the bits on bit[] for the mask string
  for(int i=0;i<second.length();i++){
    bit[second.charAt(i)] = true;
  }
 //This is not good, we can use StringBuffer
 //char[] is just for the proof of concept
 char[] result = new char[first.length()];
 for(int i=0,j=0;i<first.length();i++){
   if(bit[first.charAt(i)]==false){
     result[j] = first.charAt(i);
     j++;
   }
 }
  String resultstr = new String(result);
  System.out.println("Result - " + resultstr);
 }
}//:~