LeetCode217-存在重复元素

去重计算长度

public boolean containsDuplicate(int[] nums) {
        return Arrays.stream(nums).distinct().count()!=nums.length;
    }

排序后比较前后元素值

public boolean containsDuplicate1(int[] nums) {
        int n = 0;
        Arrays.sort(nums);
        for (int i = 0; i < nums.length-1; i++) {
            if (nums[i]==nums[i+1]){
                return true;
            }
        }
        return false;
    }