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Kotlin program to determine if a string has all unique characters

Here, we are going to learn how to check whether a string has all unique characters or not in Kotlin programming language?
Submitted by IncludeHelp, on April 28, 2020

Given a string, we have to check whether it has all unique characters or not.

Example:

    Input:
    string = "includehelp"

    Output:
    false

    Input:
    string = "abcd"

    Output:
    true

Program to determine if a string has all unique characters in Kotlin

package com.includehelp.basic

import java.util.*
import kotlin.collections.HashSet

//Main Function, entry Point of Program
fun main(args: Array<String>) {

    //Input Stream
    val sc = Scanner(System.`in`)

    //input April20.string value
    println("Input String : ")
    val str: String = sc.nextLine()


    val charHashSet: HashSet<Char> = HashSet<Char>()
    var result= false

    // iterate loop to check unique char in string
    for(i in str.indices){
        result = charHashSet.add(str[i])
        if(!result) {
            break
        }
    }
    println("Unique Char  : $result")
}

Output

Run 1:
Input String :
includehelp
Unique Char  : false
---
Run 2:
Input String :
abcd pqr
Unique Char  : true
---
Run 3:
Input String :
Hello world!
Unique Char  : false