LeetCode 217. Contains Duplicate: C++ Solution
Problem Statement
Given an array of integers, design an algorithm to find if it contains duplicates.
Return true if any value appears two or more times in the array.
Return false if every element is distinct.
Function Signature (C++):
bool containsDuplicate(vector<int>& nums)
Inputs:
nums = [1, 2, 3, 4, 1]
Outputs:
true
Inputs:
nums = [1, 2, 3, 4]
Outputs:
false
TL;DR Code Solution
bool containsDuplicate(vector<int>& nums) {
unordered_map<int, bool> map;
for (int i = 0; i < nums.size(); i++) {
if (map.count(nums[i])) {
return true;
}
else {
map[nums[i]] = true;
}
}
return false;
}