15 Jun 2024•C++ / Python / TypeScript•Easy

Contains Duplicate

Collected C++, Python, TypeScript solutions for contains duplicate. Add a dedicated write-up later if you want deeper notes.

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auto-generated entry for Contains Duplicate. the solution files are available below.

solution files

C++ contains-duplicate/synced-solution.cpp
Python contains-duplicate/synced-solution.py
TypeScript contains-duplicate/synced-solution.ts

Solution files

Python•contains-duplicate/synced-solution.py

def containsDuplicate(nums: list[int]) -> bool:
    return len(nums) != len(set(nums))

C++•contains-duplicate/synced-solution.cpp

class Solution {
public:
    bool containsDuplicate(vector<int>& nums) {
        unordered_set<int> seen;
        for (int num : nums) {
            if (seen.count(num)) {
                return true;
            }
            seen.insert(num);
        }
        return false;
    }
};

TypeScript•contains-duplicate/synced-solution.ts

function containsDuplicate(nums: number[]): boolean {
    const seen = new Set<number>();
    for (const num of nums) {
        if (seen.has(num)) {
            return true;
        }
        seen.add(num);
    }
    return false;
}