[GO] [100%] OddOccurrencesInArray (src & jUnit)

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OddOccurrencesInArray

Find the values ​​that occur on odd elements.

Task description

Given a non-empty array A consisting of N integers. The array contains an odd number of elements, and each element of the array can be paired with another element that has the same value, except for one unpaired element.

For example, in array A:

  A [0] = 9 A [1] = 3 A [2] = 9
  A [3] = 3 A [4] = 9 A [5] = 7
  A [6] = 9

• The value of the elements at indexes 0 and 2 is 9.
• The value of the elements at indexes 1 and 3 is 3.
• The value of the elements at indexes 4 and 6 is 9.
• The value of the element at index 5 is 7, and it is not paired.

Write a function:

class Solution {public int solution（int [] A）; }

Given an array A consisting of N integers that satisfy the above conditions, it returns the values ​​of the unpaired elements.

For example, given the following array A:

  A [0] = 9 A [1] = 3 A [2] = 9
  A [3] = 3 A [4] = 9 A [5] = 7
  A [6] = 9

As explained in the example above, the function should return 7.

Write an efficient algorithm for the following assumptions:

• N is an odd integer in the range [1..1,000,000].
• Each element of array A is an integer in the range [1..1,000,000,000].
• All but one of the values ​​of A occur an even number of times.

solve

Detected time complexity: O(N) or O(N*log(N))

Program OddOccurrencesInArray.java

OddOccurrencesInArray.java

    public int solution(int[] A) {
        int goal = 0;

        java.util.Arrays.sort(A);
        for (int i = 0; i < A.length -1; i++) {
            if (A[i] != A[i + 1]) {
                goal = A[i];
                break;
            }
            i++;
        }

        if (goal == 0) {
            goal =  A[A.length - 1];
        }

        return goal;
    }

jUnit OddOccurrencesInArrayTest.java

Report Candidate Report: training66EE8T-EUB