Week of 2/17/19 Cassido's interview question of the week

removeOdd.java

/**
 * Created by Kyle Long on 2/24/19.
 */
public class removeOdd {
    public static void main(String [] args){
      System.out.println(removeForOdd(new int[]{2,4,6,7,8}));
      System.out.println(removeForOdd(new int[]{4,4,4}));
      System.out.println(removeForOdd(new int[]{1,2,3,4,5,6,7}));
    }

    /**
     * Calculates array sum
     * @param arr array to sum
     * @return Array sum
     */
    public static int sum(int [] arr){
        int sum = 0;
        for(int a: arr){
            sum += a;
        }
        return sum;
    }

    /**
     * Check for odd array sum ignoring an index
     * @param index array index to ignore
     * @param arr  array to sum, ignoring index
     * @return int of sum
     */
    public static int sumIgnoreIndex(int index, int [] arr){
        int sum = 0;
        for(int i = 0; i < arr.length; i++){
            if(i != index) sum += arr[i];
        }
        return sum;
    }

    /**
     * Check for index to remove to sum array
     * @param arr array to check
     * @return index to remove to make array sum odd
     */
    public static int removeForOdd(int [] arr){
        if(sum(arr) % 2 != 0) return -1;
        for(int i = 0; i < arr.length; i++){
            if(sumIgnoreIndex(i, arr) % 2 != 0)return i;
        }
        return -1;
    }
}