WordFunnel

WordFunnel.java

import java.util.ArrayList;
import java.util.List;
import java.util.Objects;

import static java.util.stream.Collectors.toList;

public class WordFunnel {
  public static void main(final String... args) {
    if (funnel("leave", "eave")) {
      System.out.println("funnel");
    }

  }

  private static boolean funnel(final String first, final String second) {
    final List<Integer> firstList = first.chars().boxed().collect(toList());
    for (int i = 0; i < firstList.size(); i++) {
      final List<Integer> tempList = getSublist(firstList, i);

      if (join(tempList).equals(second)) {
        return true;
      }
    }
    return false;
  }

  private static List<Integer> getSublist(final List<Integer> firstList, final int i) {
    final List<Integer> tempList = new ArrayList<>(firstList);
    tempList.remove(i);
    return tempList;
  }

  private static String join(final List<Integer> tempList) {
    final List<String> chars = tempList.stream().map(x -> (char) x.intValue()).map(Objects::toString).collect(toList());

    return String.join("", chars);
  }
}

WordFunnelKotlin.kt

import java.lang.String.join
import java.util.*
import java.util.stream.Collectors.toList


fun main(args: Array<String>) {
    if(funnel("leave", "eave")) {
        System.out.println("funnel")
    }

}

private fun funnel(first: String, second: String) =
        first.chars().boxed().collect(toList()).run {
            (0..size).any {
                getSublist(it).joinChars() == second
            }
        }


private fun List<Int>.getSublist(i: Int) =
        ArrayList<Int>(this).apply {
            removeAt(i)
        }

private fun List<Int>.joinChars() =
        stream().map { it.toChar().toString() }.collect(toList<String>()).let {
            join("", it)
        }