Programming Test - Codility - Dominator [closed]

Answer 1

Adding a Java 100/100 O(N) time with O(1) space:

// you can also use imports, for example:
import java.util.Stack;

// you can write to stdout for debugging purposes, e.g.
// System.out.println("this is a debug message");

class Solution {
    public int solution(int[] A) {
        // write your code in Java SE 8
        int count = 0;
        Stack integerStack = new Stack();
        for (int i = 0; i < A.length; i++) {
            if (integerStack.isEmpty()) {
                integerStack.push(A[i]);
            } else if (integerStack.size() > 0) {
                if (integerStack.peek() == A[i])
                    integerStack.push(A[i]);
                else
                    integerStack.pop();
            }
        }
        if (!integerStack.isEmpty()) {
            for (int i = 0; i < integerStack.size(); i++) {
                for (int j = 0; j < A.length; j++) {
                    if (integerStack.get(i) == A[j])
                        count++;
                    if (count > A.length / 2)
                        return j;
                }
                count = 0;
            }
        }
        return -1;
    }
}

Here is test result from codility.