Contains Duplicate

leetcode.com/problems/contains-duplicate/

Contains Duplicate - LeetCode

 

import java.util.*;
 
class Solution {
    public boolean containsDuplicate(int[] nums) {
        Map<Integer, Integer> map = new HashMap<>();
        boolean isExisted = false;
        for (int i = 0; i < nums.length; i++) {
            if (map.containsKey(nums[i])) {
                return isExisted = true;
            } else {
                map.put(nums[i], i);
            }
        }
        return isExisted;
        
    }
}