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Java-based LeetCode algorithm problem solutions, regularly updated

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package g0201_0300.s0217_contains_duplicate;

// #Easy #Top_Interview_Questions #Array #Hash_Table #Sorting #Data_Structure_I_Day_1_Array
// #Programming_Skills_I_Day_11_Containers_and_Libraries #Udemy_Arrays
// #2022_07_02_Time_6_ms_(96.68%)_Space_54.4_MB_(94.38%)

import java.util.HashSet;
import java.util.Set;

/**
 * 217 - Contains Duplicate\.
 *
 * Easy
 *
 * 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 
 *
 * **Example 3:**
 *
 * **Input:** nums = [1,1,1,3,3,4,3,2,4,2]
 *
 * **Output:** true 
 *
 * **Constraints:**
 *
 * *   1 <= nums.length <= 10⁵
 * *   -10⁹ <= nums[i] <= 10⁹
**/
public class Solution {
    public boolean containsDuplicate(int[] nums) {
        Set set = new HashSet<>();
        for (int n : nums) {
            if (set.contains(n)) {
                return true;
            }
            set.add(n);
        }
        return false;
    }
}