Here, We see Contains Duplicate problem Solution. This Leetcode problem is done in many programming languages like C++, Java, JavaScript, Python, etc., with different approaches.

Contains Duplicate LeetCode Solution
Problem Statement ->
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
Contains Duplicate Leetcode Solution C++ ->
class Solution {
public:
bool containsDuplicate(vector<int>& nums) {
if (nums.empty()) { return false; }
unordered_map<int,int> mp;
for (int i : nums) {
if (++mp[i] > 1) {
return true;
}
}
return false;
}
};
Code language: C++ (cpp)
Contains Duplicate Leetcode Solution Java ->
class Solution {
public boolean containsDuplicate(int[] nums) {
if(nums==null || nums.length==0)
return false;
HashSet<Integer> hset = new HashSet<Integer>();
for(int idx: nums){
if(!hset.add(idx)){
return true;
}
}
return false;
}
}
Code language: Java (java)
Contains Duplicate Leetcode Solution JavaScript ->
var containsDuplicate = function(nums) {
const s = new Set(nums);
return s.size !== nums.length
};
Code language: JavaScript (javascript)
Contains Duplicate Leetcode Python ->
class Solution(object):
def containsDuplicate(self, nums):
return len(nums) != len(set(nums))
Code language: Python (python)