Codility 2.PermMissingElem

class Solution {
   public int solution(int[] A) {
        // write your code in Java SE 8
        if(A.length<2){
            return 0;
        }else{
            int sorted[] = bubbleSort(A);
            for(int i=0;i<sorted.length;i++){
                if(i==sorted.length-1){
                    return 0;
                }else{
                    int difference = sorted[i+1]-sorted[i];
                    if(difference==2){
                        return sorted[i]+1;
                    }
                }
            }
        }
        return 0;
    }
    
    public int[] bubbleSort(int[] number) {
        int temp = 0;
        for (int i = 0; i < number.length - 1; i++){
            for (int j = 0; j < number.length - 1 - i ; j++){
                if (number[j] > number[j + 1]) {
                    temp = number[j];
                    number[j] = number[j + 1];
                    number[j + 1] = temp;
                } //if end                               
            }                
        }
        return number;
    }
}