Description Link to heading
Solution Link to heading
We can use unordered_map to record the number of ocurrence of each integer and slide window accrording the unordered_map.
Code Link to heading
class Solution {
public:
bool containsNearbyDuplicate(vector<int>& nums, int k) {
unordered_map<int, int> mp;
for (int i = 0; i < nums.size(); i++) {
if (mp.find(nums[i]) != mp.end()) {
if (i - mp[nums[i]] <= k)
return true;
else
mp[nums[i]] = i;
} else {
mp[nums[i]] = i;
}
}
return false;
}
};