LeetCode 217. There are duplicate elements

Give you an array of integers nums . If any value appears in the array At least twice , return true ; If each element in the array is different from each other , return false .
 

Example 1：

Input ：nums = [1,2,3,1]
Output ：true
Example 2：

Input ：nums = [1,2,3,4]
Output ：false
Example  3：

Input ：nums = [1,1,1,3,3,4,3,2,4,2]
Output ：true
 

Tips ：

1 <= nums.length <= 105
-109 <= nums[i] <= 109

source ： Power button （LeetCode）
link ：https://leetcode.cn/problems/contains-duplicate
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Answer key ：

class Solution {
    public static boolean containsDuplicate(int[] nums) {
        Map<Integer,Integer> map = new HashMap<>();
        for (int i = 0; i < nums.length; i++) {
            map.put(nums[i], map.getOrDefault(nums[i], 0) + 1);
        }
        for (int value: map.values()
             ) {
            if (value > 1) return true;
        }
        return false;
    }
}