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Toyota Programming Contest 2023#5（AtCoder Beginner Contest 320） Announcement
By atcoder_official, history, 6 days ago, In English

We will hold Toyota Programming Contest 2023#5（AtCoder Beginner Contest 320）.

We are looking forward to your participation!

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6 days ago, # |
  Vote: I like it +4 Vote: I do not like it

Why downvotes are in the announcement? don't be a kid!

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    6 days ago, # ^ |
      Vote: I like it -9 Vote: I do not like it

    why downvote ;(((

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5 days ago, # |
  Vote: I like it -36 Vote: I do not like it

Hope to solve A, B, C.

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5 days ago, # |
  Vote: I like it -36 Vote: I do not like it

Hope to solve A, B, C, D.

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5 days ago, # |
  Vote: I like it -36 Vote: I do not like it

Hope to solve A, B, C, D, E.

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5 days ago, # |
  Vote: I like it -36 Vote: I do not like it

Hope to Solve A, B, C, D.

GOD BLESSING ME!!!

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5 days ago, # |
  Vote: I like it -36 Vote: I do not like it

Hope to solve A,B,C.

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5 days ago, # |
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HOPE to solve A....This is my first atcoder contest ;}

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5 days ago, # |
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Hope to solve A to D.

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5 days ago, # |
  Vote: I like it -12 Vote: I do not like it

Why can't I pass problem D!!! The contest will be finished in 18 min!

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5 days ago, # |
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Bruh, C was so annoying. Solved D in like ~10 minutes, but wasted so much time thinking for C :<

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5 days ago, # |
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what is mistake in my code for D

https://atcoder.jp/contests/abc320/submissions/45643786

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5 days ago, # |
  Vote: I like it +1 Vote: I do not like it

Well, I spend 30 min to understand what C was saying!

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5 days ago, # |
  Vote: I like it 0 Vote: I do not like it

Task G it seems flow without any optimization passed.

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5 days ago, # |
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can anybody please tell me a counter test case for C problem according to my code. or where my logic is wrong?

Code
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    5 days ago, # ^ |
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    Have you consider when a certain digits are located in the same position?

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      5 days ago, # ^ |
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      I guess, I didn't comprehend problem fully.

      If possible, tell me a counter case please

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5 days ago, # |
← Rev. 2   Vote: I like it 0 Vote: I do not like it

Nice C. I did not thought of direct simulation. I thought to fix one string, find i th char in other two strings. Equal index in all 3 ,in one of 2 strings and not euqual indexes, all those cases just made my implementation harder.

Equal Numbers,alphabets,indexes,maximms,minimums are the tools to make question harder and sometimes even annoying if you handle it in wrong way

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5 days ago, # |
  Vote: I like it +1 Vote: I do not like it

Me wasting 40 minutes on C not realizing there were only 3 slot machines. :(

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5 days ago, # |
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Problem C, remains me I am still not good at logical thinking

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    5 days ago, # ^ |
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    I think it has 2 solutions.one with observation and another solution which need a bit of implmentation. This reminds us that we both are good for nothing.

    Note I did not solve C even after pactising year. I know c++ since 2016.

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5 days ago, # |
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For $$$C$$$, You can just make 3 consecutive copies of each string ($$$S_i =S_i + S_i + S_i$$$).

Try every digit[0:9] and if you found 3 different indices have the same digit, minimize the maximum index with the answer . Code : 45651190

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5 days ago, # |
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can somebody tell me why i am stuck in problem D

https://atcoder.jp/contests/abc320/submissions/45651936

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5 days ago, # |
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in the editorial of F: in the fourth case we need to iterate right? so how the complexity will stay O(n^3) ? https://atcoder.jp/contests/abc320/editorial/7169

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    4 days ago, # ^ |
      Vote: I like it +16 Vote: I do not like it

    This will happen only when $$$k=H$$$, which is $$$O(H)$$$ for every $$$dp_{i,j}$$$.

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4 days ago, # |
  Vote: I like it 0 Vote: I do not like it

Sub AtCoder it locked my account without any email or notice.

fu!

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4 days ago, # |
← Rev. 3   Vote: I like it +4 Vote: I do not like it

The data of question C is suggested to be strengthened

this is the hack input

8
12221222
13313331
44414414

answer: 

4

Output the wrong answer '6' but accepted code. https://atcoder.jp/contests/abc320/submissions/45625948

This hack can block some greedy algorithms, including me.

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4 days ago, # |
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Whats the mistake in my code for Question E? https://atcoder.jp/contests/abc320/submissions/45637747

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4 days ago, # |
← Rev. 2   Vote: I like it 0 Vote: I do not like it

I can't understand the C problem. Why the answer of testcase:

20 01234567890123456789 01234567890123456789 01234567890123456789

is 20? can't we just stop at 0 seconds so all reels show 0?

Edit: nvm, I got it, he can press only one button at any given second.

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36 hours ago, # |
← Rev. 3   Vote: I like it 0 Vote: I do not like it

For problem G: (1) (2)

The (1) code shows about 7 times slower than (2) for test 5, and it gets TLE. (2) is AC, and the difference between (1) and (2) is the way of adding the element to the b array: for (1), i use (line 135 to 141)

        for(int i=1; i<=n; i++){
            int cur = 0;
            while(b[i].size() < n){
                b[i].push_back(b[i][cur] + m);
                cur++;
            }
        }

for (2) (line 134 to 137):

            int ts = tmp.size();
            for(int k=0; k<n; k++){
                b[i].push_back(tmp[k % ts] + m * (k / ts));
            }

Why is (1) so slow? Very thanks!

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