import java.util.*;
/**
 * Created by leon on 1/29/18.
 */
public class StringArrayUtils {
    /**
     * @param array array of String objects
     * @return first element of specified array
     */ // TODO
    public static String getFirstElement(String[] array) {
        return array[0];
    }

    /**
     * @param array array of String objects
     * @return second element in specified array
     */
    public static String getSecondElement(String[] array) {
        return array[1];
    }

    /**
     * @param array array of String objects
     * @return last element in specified array
     */ // TODO
    public static String getLastElement(String[] array) {
        return array[array.length-1];
    }

    /**
     * @param array array of String objects
     * @return second to last element in specified array
     */ // TODO
    public static String getSecondToLastElement(String[] array) {
        return array[array.length-2];
    }

    /**
     * @param array array of String objects
     * @param value value to check array for
     * @return true if the array contains the specified `value`
     */ // TODO
    public static boolean contains(String[] array, String value) {
        boolean answer = false;
        for(String x : array){
            if(x.equals(value)){
                answer = true;
            }

        }
        return answer;
    }

    /**
     * @param array of String objects
     * @return an array with identical contents in reverse order
     */ // TODO
    public static String[] reverse(String[] array) {
        /*   StringBuilder x = new StringBuilder(array.toString());
        x.reverse();
        String[] answer = new String[x.toString().split(" ").length](x.reverse().toString());

         */   
        String[] x = new String[array.length];
        int p = 0;
        for(int i = array.length-1; i >= 0; i--){           
            x[p] = array[i];
            p++;
        }
        return x;
    }

    /**
     * @param array array of String objects
     * @return true if the order of the array is the same backwards and forwards
     */ // TODO
    public static boolean isPalindromic(String[] array) {
        int x = 0;
        int y = array.length - 1;
        boolean answer = true;
        if(array.length % 2 == 0){
            while(x < y && answer == true){
                if(array[x] == array[y]){
                    x++;
                    y--;
                } else{
                    answer = false;
                }
            }
        } else{
            while(x != y && answer == true){
                if(array[x] == array[y]){
                    x++;
                    y--;
                } else{
                    answer = false;
                }
            }
        }

        /*      if(reverse(array) != array){
        return false;
        }
        return true;

         */
        return answer;
    }

    /**
     * @param array array of String objects
     * @return true if each letter in the alphabet has been used in the array
     */ // TODO
    public static boolean isPangramic(String[] array) {
        return false;
    }

    /**
     * @param array array of String objects
     * @param value value to check array for
     * @return number of occurrences the specified `value` has occurred
     */ // TODO
    public static int getNumberOfOccurrences(String[] array, String value) {
        int counter = 0;
        for(String x : array){
            if(x == value){
                counter++;
            }
        }
        return counter;
    }

    /**
     * @param array         array of String objects
     * @param valueToRemove value to remove from array
     * @return array with identical contents excluding values of `value`
     */ // TODO
    public static String[] removeValue(String[] array, String valueToRemove) {
        ArrayList<String> x = new ArrayList<String>((Arrays.asList(array)));
        for(String h : x){
            if(h == valueToRemove){
                x.remove(x.indexOf(h));
            }
        }

        String[] q = new String[x.size()];
        q = x.toArray(q);
        return q;
    }

    /**
     * @param array array of chars
     * @return array of Strings with consecutive duplicates removes
     */ // TODO
    public static String[] removeConsecutiveDuplicates(String[] array) {
        ArrayList<String> x = new ArrayList<String>();
        // String[] y = new String[];
        for(int i = 0; i < array.length; i++){
            if(array[i] == array[i + 1]){
                x.add(array[i]);
            }	
        }
        String[] y = new String[x.size()];
        x.toArray(y);
        return y;
    }

    /**
     * @param array array of chars
     * @return array of Strings with each consecutive duplicate occurrence concatenated as a single string in an array of Strings
     */ // TODO
    public static String[] packConsecutiveDuplicates(String[] array) {
        return null;
    }

}