Top K Frequent Elements | Heap | Bucket Sort | AMAZON | Leetcode 347 | Explanation | Live Coding

=======2 APPROACHES + FROM INTUITION BUILDING TO COMPLETE SOLUTION=======
Hi everyone, this is the 6th video of our Heap Playlist.
In this video we will try to solve a very good and famous Problem “Top K Frequent Elements”.
We will do live coding after explanation and see if we are able to pass all the test cases.

Share your learnings on LinkedIn, Twitter (X), Instagram, Facebook(Meta) with hashtag hashtag #codestorywithmik & feel free to tag me.

Problem Name : Shortest Bridge
Company Tags : AMAZON

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#coding #helpajobseeker #easyrecipes #leetcode #leetcodequestionandanswers #leetcodesolution #leetcodedailychallenge #leetcodequestions #leetcodechallenge #hindi #india #hindiexplanation #hindiexplained #easyexplaination #interview #interviewtips
#interviewpreparation #interview_ds_algo #hinglish

[oqant]

#5:58 at this point i understood why min heap is i solved this via max i was confused which one to use

[udayshankar-ev]

Your explantion is very clear, after Striver i only follow you.

[userfg]

Thanks alot! Even after watching some resources about bucket sort, I was unable to wrap up my mind around it but you made it easy for me and finally solved daily problem on leetcode with bucket sort as you suggested to do at the end of your video.

[technologicalvivek]

bhaiya aap samjate bahut aacha ho.Tough ko bhi easy kar dete ho.Thank you for this lecture.

[BiswajitRout-dlry]

damn the second approach is very unique i solve lot of question but i am not able think this way i learned the new technique (bucket sort) thanks bhiya ....

[sidharthdhiman]

great sir, maine bhi yahi socha priority quey and woh reverse map ka, reverese map wale me tle arha tha kafi time lagaya thik nhi hua and yeh priortiy queu wale me mai woh class comparator ka soch rha tha but usme bhi thik nhi hua ab apka video tdekha toh galti samjh ayi

and thanx sir time compleixty discussion ke liye bhi yeh sabse best hai,

[JJ-tpdd]

bhai if you want to make the dp series a paid one, I'll be happy to join. I felt really bad yesterday after seeing your shorts. If it helps you and the channel in any way, please make the dp series a paid course. You deserve more subscribers and all the love ❤💙

[ManojKrVerma-vwdx]

Second solution is new for me. ThankYou

[wearevacationuncoverers]

I knew this guys will be adding extra more approach. Thanks for the bucket sort solution

[susantamandal]

Hi MIK, thank you for the details explanations for all the different problems. I am now one of your follower :)
I have a small doubts, at time 13:29, the PriorityQueue add operations will happen n times or k times. because irrespective of the k, we are adding all the items.

[vengalrao]

You deserve subs more bhaiyya 😢❤
Big Fan of your hardwork and consistency.

[tanishchordia]

Mik, In one of previous lectures you taught how to make a customize seperator acc. to the problem so i used that still did this with max heap making lambda as my custom operator
thank you🎉

[JJ-tpdd]

Java Solution:

Priority Queue:
class Pair{

int first;
int second;
public Pair(int first, int second){

this.first = first;
this.second = second;
}
}

class Solution {
public int[] topKFrequent(int[] nums, int k) {

Map<Integer, Integer> mp = new HashMap<>();
for(int num : nums) {
mp.put(num, mp.getOrDefault(num, 0)+1);
}
PriorityQueue<Pair> pq = new PriorityQueue<Pair>((x, y) -> x.first - y.first);

for(var entry : mp.entrySet()) {
int value = entry.getKey();
int freq = entry.getValue();

pq.offer(new Pair(freq, value));

if(pq.size() > k){
pq.poll();
}
}

int[] result = new int[k];
for(int i=0; i<k; i++){
result[i] = pq.poll().second;
}
return result;
}
}

Bucket Sort:
class Solution {
public int[] topKFrequent(int[] nums, int k) {
int n = nums.length;

Map<Integer, Integer> mp = new HashMap<>();
for(int num : nums){
mp.put(num, mp.getOrDefault(num, 0) + 1);
}
List<Integer>[] bucket = new ArrayList[n + 1];

for(int value : mp.keySet()){
int freq = mp.get(value);
if(bucket[freq] == null){
bucket[freq] = new ArrayList();
}
bucket[freq].add(value);
}

int res[] = new int[k];
int index = 0;
for(int i = bucket.length - 1; i >= 0; i--){
if(bucket[i] != null){
for(int v : bucket[i]){
res[index++] = v;
if(index == k) return res;
}
}
}
return res;
}
}

[ajit]

Thank You bro. One request please make a detail video on comparator in c++

[chad._life]

thankyou for kind help
we can solve it in quite simple way also this is how
C++

class Solution {
public:
vector<int> topKFrequent(vector<int>& nums, int k) {
unordered_map<int, int>mp;
vector<int>ans;
priority_queue<pair<int, int>>pq;
for(auto i:nums){
mp[i]++;
}
for(auto &it:mp){
pq.push({it.second, it.first});
}
while(k--){
int temp=pq.top().second;
pq.pop();
ans.push_back(temp);
}
return ans;
}
};

[shashwatchawla]

// Brute force solution

class Solution {
public:

static bool cmp( const pair<int, int>& a, const pair<int, int>& b) {
return a.second > b.second;
}

vector<int> topKFrequent(vector<int>& nums, int k) {



map<int, int>mp;
for(auto x:nums)
{
mp[x]++;
}

vector<pair<int, int>>v(mp.begin(), mp.end());


sort(v.begin(), v.end(), cmp );

vector<int>ans;

for(int i=0;i<k;i++)
{
ans.push_back(v[i].first);
}

return ans;



}
};

[amankunwar]

make a video of k closet point to origin

[udaykumarchetla]

Bro ur there on codeforces and codechef?

[DivVj]

Can you make the playlist specific to the companies? Like for questions which was asked in Microsoft would be gathered in one playlist If possible.

[udaykumarchetla]

Mik, please use a mic. Voice is low without head phones.