Every announcement of Div3 round from Supermagzzz, Stepavly and MikeMirzayanov makes me happy!

Good luck everyone !!!

Sick, I miss div 3 contests so much, looking forward to participating into this!

Excited

is div3 rated for someone with current rating < 1600 but his max rating >= 1900 ??

Edit : sorry i didn't see this Regardless of whether you are a trusted participant of the third division or not, if your rating is less than 1600, then the round will be rated for you.

Is the rated cap for rounds based on the user's rating at the time of the contest or at the time of the registration?

I tried searching for some relevant blog but couldn't find one.. Thanks in advance :)

Yah Codeforces Hey!

Yah hum coders hey

Yaha Cowding ho rahi hey!

Finally, a div3 round that I missed so much

1

Previous rating change unrolled, will this contest be rated for me ?

Back to back cf Round :D

Judging by my very poor performance of the last round(spoiler: never enter a round 40 minutes after it started:)) i think that this round should be rated for me. Are the new ratings coming until the start of this div3?

will the new ratings come before div3 or not ??

From the last contest there seems to be less participation because of busy schedules and lot of assignments of college.

As a participant, I wish no "Wrong Answer On Test x" situation.

This is my first time to compete in CF. good luck. 祝我好运！

Okay

Wait is over ❤ Finally div 3 after long time

Why there is a massive difference between last and this time DIV3 contest??

Thank you ! perfect time for div3

Wtfffff Muffinhead 6 problems in 9 minutes how is this even possible !!

I am unable too see problems or register can someone help?

Positive delta YES!!!!

Is it just me or these div3 rounds have become wayy too easy.

is this a div4?

wrong answer using segment tree on g why? Here:107616153

invented ! =discovered.

Supermagzzz's DIV 3 are easier as compared to vovuh's.

speedforces :(

I was not particularly quick today but still solved all problems and recorded a screencast with explanations

The difficulty from A-E is in decreasing order

Felt more like a Leetcode Contest without its final problem

Can't we solve problem f without using the concept of hashing? initially, I was thinking to declare an array of size 10^9. later realized that it would give any runtime error or memory limit exceed.

Is there any way other than hashing or map to solve f ?

My solution for problem C outputs "NO" in my local device while outputs "YES" when I submit, for input 34. It tried with brackets also, but results are the same. It showing 'wrong answer for test 1'.

my solution is: https://codeforces.com/contest/1490/submission/107615310

Why this solution (for problem F) TLE on test 2. I think the time complexity is O(nlogn): https://codeforces.com/contest/1490/submission/107618301

Does someone know a test where this solution for G might fail? : https://codeforces.com/contest/1490/submission/107619800

is all problem of div 3 is of equal points or C(poihnts)>B

Spent 35 minutes on this bug. fml.

What the heck is Unexpected verdict

Problem C why my hacking verdict is 'Unexpected verdict'

Input :
100
1000000000000
1000000000000
1000000000000
1000000000000
1000000000000
...

Different problem statements, but very similar question to E

Finally very good Div.**3** contest! All who are Div.2-level could solve almost all problems.

How to Solve G?

Easy round, but I found my mistake on G 3 minutes before the end :(

Can some one tell me where I am wrong in problem B.

for i in l:
    ll.append(i%3)

c0 = ll.count(0)
c1 = ll.count(1)
c2 = ll.count(2)
d = n//3
#print(c0,c1,c2)
#print(d)
m = max(c0,c1,c2)
if m==c0:
    ans = c0-d
    if c1+c0-d>d:
        ans = ans + c1 + c0 -d  - d
    else:
        ans = ans + 2*(d - c1-c0 +d)
elif m==c1:
    ans = c1-d
    if c2 + c1-d>d:
        ans = ans + c2 + c1 -d -d
    else:
        ans = ans + 2*(d - c2 -c1 +d)
else:
    ans = c2-d
    if c0 + c2 -d >d:
        ans =ans + c0 + c2 - d -d
    else:
        ans =ans + 2*(a - c0 - c2 +d)
print(ans)

I am just removing the extra part (present count — the equal number of c0,c1,c2 that shud be there) from maximuum of c0,c1,c2 and adding it to next one among them ..and then again removing the extra from that part and adding it to next part. But I ma getting WA on runtime error on tc 2. ples help Thanks in advance.

Easy round, but I found my mistake on G 3 minutes before the end :(

Bruteforces!!

Those who have just started reading Binary Search , they must try to solve problems C , E , G. All 3 of them decent problems to start with.

if(c2>n/3)
	  {
	  	c0=c0+c2-n/3;
	  	cout<<(c2-n/3)+abs(c0-n/3)<<"\n";
	  }
	  else
	  {
	  	c1=c1-(n/3-c2);
	  	cout<<(n/3-c2)+abs(c1-n/3)<<"\n";
	  }

Why this approach is wrong in B

Here’s my attempt to screencast this Div3 contest, where I have explained the solutions to the problems later. It’s my first ever screencast, and any suggestions would be helpful.

https://www.youtube.com/watch?v=fbv5NKA9t9c

I hope you like it.

Is this round rated ? as it is showing in unrated contest in my performance graph in profile section

I felt that the problems were slightly easier than usual today but really enjoyed the contest! Thanks for the great round.

G is a harder version of this problem

I uploaded a screencast: https://youtu.be/InbURHKu_Lk

Is anyone here who solved F using Binary or ternary search?

To not keep you waiting, the ratings updated preliminarily. In a few hours, I will remove cheaters and update the ratings again!

Why unordered map gets tle in F?

How to approach problem F if instead of "either zero or C times" we consider "multiple of C times" in the problem statement? (I misread it during the contest).

My F got accepted in 100 ms but 2000 ms after hacking phase. Collision between values is the reason for this because of hash function?

good contest

Rating got changed again ? Something happened?

Hi, Guys! I am stucked on #F on 12 test with time limit. No ideas to fix it. May u help, please?

int t;
    cin >> t;

    while (t--)
    {
        ll n;
        cin >> n;
        vector<ll> a(n);
        unordered_map<ll, ll> m;
        for (auto& x : a)
        {
            cin >> x;
            ++m[x];
        }

        vector<ll> cnts;
        ll sum = 0;
        ll cnts_size = 0;
        for (auto x : m)
        {
            cnts.push_back(x.second);

            sum += x.second;
            ++cnts_size;
        }

        //countSort(cnts);
        sort(cnts.begin(), cnts.end());

        ll c_val = sum - cnts_size *cnts[0];
      
        for (ll i = 1; i < cnts_size; ++i)
        {
       
            if (cnts[i] == cnts[i - 1]) continue;
            ll val = sum - (cnts_size - i) * cnts[i];
            c_val = min(val, c_val);

        } 

        cout << c_val << endl;
        
    }

Why were solutions rejudged on uphacks?