package kent.alg.leetcode;

import java.util.HashMap;

import org.junit.jupiter.api.Test;

public class SingleNumber {

public int singleNumber(int[] nums) {

HashMap<Integer, Integer> map = new HashMap<Integer, Integer>();

for(int i=0; i<nums.length; i++) {

if(map.containsKey( nums[i] )) {

int counter = map.get(nums[i]) + 1;

map.put(nums[i], counter);

}

else {

map.put(nums[i], 1);

}

}

for(Object key : map.keySet()) {

int result = map.get(key);

if(result == 1)

return (int) key;

}

return -1;

}

@Test

public void Test() {

int[] nums = {4,1,1,0,0,2,1,2};

System.out.println(singleNumber(nums));

}

}