Data Structure #01

Given an integer array nums, return true if any value appears at least twice in the array, and return false if every element is distinct.

?

Example 1:

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

Example 2:

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

Solution

class Solution {
    public boolean containsDuplicate(int[] nums) {
        Set<Integer> intset = new HashSet<>();
        for(int num : nums){
            if(intset.contains(num))
            return true;
            intset.add(num);    
        }
        return false;
}
}