Find first Unique Char in String












0

















Given a string, find the first non-repeating character in it.



Example



i/p - Vikrant
o/p - None

i/p - VikrantVikrant
o/p - Some(V)



Scala implementation:





object FirstUniqueChar extends App {
def firstUnique(s: String): Option[Char] = {
val countMap = (s groupBy (c=>c)) mapValues(_.length)
def checkOccurence(s1: String ): Option[Char] = {
if (countMap(s1.head) > 1) Some(s1.head)
else if (s1.length == 1) None
else checkOccurence(s1.tail)
}
checkOccurence(s)
}
println(firstUnique("abcdebC"))
println(firstUnique("abcdef"))
}


I also have a followup question. What is the recommended way if I do not want to solve this problem with recursion? Instead of using the checkOccurence method I can traverse through the string and break when I find the first element with a count more than 1. But that will require a break, which is discouraged in Scala.










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    0

















    Given a string, find the first non-repeating character in it.



    Example



    i/p - Vikrant
    o/p - None

    i/p - VikrantVikrant
    o/p - Some(V)



    Scala implementation:





    object FirstUniqueChar extends App {
    def firstUnique(s: String): Option[Char] = {
    val countMap = (s groupBy (c=>c)) mapValues(_.length)
    def checkOccurence(s1: String ): Option[Char] = {
    if (countMap(s1.head) > 1) Some(s1.head)
    else if (s1.length == 1) None
    else checkOccurence(s1.tail)
    }
    checkOccurence(s)
    }
    println(firstUnique("abcdebC"))
    println(firstUnique("abcdef"))
    }


    I also have a followup question. What is the recommended way if I do not want to solve this problem with recursion? Instead of using the checkOccurence method I can traverse through the string and break when I find the first element with a count more than 1. But that will require a break, which is discouraged in Scala.










    share|improve this question



























      0












      0








      0










      Given a string, find the first non-repeating character in it.



      Example



      i/p - Vikrant
      o/p - None

      i/p - VikrantVikrant
      o/p - Some(V)



      Scala implementation:





      object FirstUniqueChar extends App {
      def firstUnique(s: String): Option[Char] = {
      val countMap = (s groupBy (c=>c)) mapValues(_.length)
      def checkOccurence(s1: String ): Option[Char] = {
      if (countMap(s1.head) > 1) Some(s1.head)
      else if (s1.length == 1) None
      else checkOccurence(s1.tail)
      }
      checkOccurence(s)
      }
      println(firstUnique("abcdebC"))
      println(firstUnique("abcdef"))
      }


      I also have a followup question. What is the recommended way if I do not want to solve this problem with recursion? Instead of using the checkOccurence method I can traverse through the string and break when I find the first element with a count more than 1. But that will require a break, which is discouraged in Scala.










      share|improve this question


















      Given a string, find the first non-repeating character in it.



      Example



      i/p - Vikrant
      o/p - None

      i/p - VikrantVikrant
      o/p - Some(V)



      Scala implementation:





      object FirstUniqueChar extends App {
      def firstUnique(s: String): Option[Char] = {
      val countMap = (s groupBy (c=>c)) mapValues(_.length)
      def checkOccurence(s1: String ): Option[Char] = {
      if (countMap(s1.head) > 1) Some(s1.head)
      else if (s1.length == 1) None
      else checkOccurence(s1.tail)
      }
      checkOccurence(s)
      }
      println(firstUnique("abcdebC"))
      println(firstUnique("abcdef"))
      }


      I also have a followup question. What is the recommended way if I do not want to solve this problem with recursion? Instead of using the checkOccurence method I can traverse through the string and break when I find the first element with a count more than 1. But that will require a break, which is discouraged in Scala.







      strings recursion interview-questions functional-programming scala






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      edited 17 mins ago









      Jamal

      30.3k11116226




      30.3k11116226










      asked 2 hours ago









      vikrantvikrant

      807




      807






















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