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Print the first unique or non-repeated character from a string

Here, we have to print the first character which is not repeated in the given string.

eg:-

  • google  ( moving from left to right 'g' is repeated, 'o' is also repeated, 'l' and 'e' are not repeated. but  'l' comes first. So, 'l' is the required answer.)
  • facebook ( moving from left to right first we have to check for character 'f', in the given string "facebook"  'f' comes only one time. So, 'f' is the correct answer.).



Note:-

In Java, to find the position of a character in a string we have two methods 
(i) index( ) and (ii) lastIndexOf( ).

1. index( ) :- It finds the first index position of a character.

2. lastIndexOf( ) :- It finds the last index position of a character. 



Solution:-
For Java solution we can use the above two methods. If the first position and last position of a character is same it means that character is not repeated in that string.


For Python Solution we can count the occurrence of a character in that string. If the count of a character in a string is only 1 it means that character is non-repeated.

Java

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 import java.util.Scanner;

 public class NonRepeatedAndUniqueCharacters 
 {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        String s = sc.nextLine();
        for (int i = 0; i < s.length(); i++)
        {
            char ch = s.charAt(i);
            if (s.indexOf(ch)==s.lastIndexOf(ch))
            {
                System.out.println(ch);
                break;
            }

        }
    }
 }

Python

input_str = input("Enter String:")
for char in input_str:
    if input_str.count(char) == 1:
        print(char)
        break

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