Missing Character

Problem Statement:
        Given a input string and  range , find the missing character.

For Example,

Input String:   "bCDfa"
Range : 'a' to 'f''

Therefore missing character is 'e'.

Solution:
Run Source Code
      We will be using hashtable concept here. Below is the implementation.

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/** * Given Input String and range find the missing character * @author Prateek */ public class MissingChar { private static final int offset = 97; private static final int PRESENT = 1; private static final int BLANK = 32; public static char missingChar(String input, char startChar, char endChar) { if (input == null || input.equals("")) return (char) BLANK; int start = (int) startChar, end = (int) endChar; int[] hash = new int[end - start+1]; input=input.toLowerCase(); int i=0; for(;i<input.length();i++){ int item =(int)input.charAt(i); hash[item - offset]=PRESENT; } i=0; for(;i<hash.length;i++){ if(hash[i]!=PRESENT) return (char)(i+offset); } return (char)BLANK; } public static void main(String[] args) { String s="bcADf"; System.out.println(missingChar(s, 'a', 'f')); } }

Please comment and post your suggestions.
Happy Coding !!:)