atcoder_official's blog

AtCoder Beginner Contest 477 Announcement
By atcoder_official, history, 6 weeks ago, In English

We will hold UNICORNProgramming Contest2026(AtCoder Beginner Contest 477).

We are looking forward to your participation!

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6 weeks ago, hide # |
 
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Hopefully I solve A-D this time, goodluck everyone

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6 weeks ago, hide # |
 
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No convolution problems plz

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6 weeks ago, hide # |
 
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No trash round plz.

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6 weeks ago, hide # |
 
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Why are all scores "???" on Atcoder

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6 weeks ago, hide # |
 
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Why are all the scores for this contest's problems '???'?

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6 weeks ago, hide # |
 
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really want to solve E!!!!

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6 weeks ago, hide # |
 
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I hope to answer questions ABCDE 5.

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6 weeks ago, hide # |
 
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Good morning

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6 weeks ago, hide # |
 
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I can solve D but can't solve C?

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6 weeks ago, hide # |
 
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1

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6 weeks ago, hide # |
 
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Is the difficulty of this ABC test really the same as last time? I think it's much harder than the last one.

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6 weeks ago, hide # |
 
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Rating this contest is the worst choice I've ever made.

I didn't read C carefully so I try to use KMP to solve the problem.

D struck me 40min and I have no time to write F(a simple Nested Segment Tree).

Hope I can get any ratings.

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    6 weeks ago, hide # ^ |
     
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    Can you explain your idea for F?

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      6 weeks ago, hide # ^ |
       
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      By using a Nested Segment Tree(2D Segment Tree).

      And then the problem turned to be a model problem.

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        6 weeks ago, hide # ^ |
        ← Rev. 5  
        Vote: I like it -8 Vote: I do not like it

        what is even 2D segment tree I mean could you please explain on how it work in this setting of problem F I'm interest in the idea you share brother,

        Spoiler

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6 weeks ago, hide # |
 
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i took way too long for C :sob:

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6 weeks ago, hide # |
 
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in D, what happens to the color of the square when a tile is placed on it. I mean what is the final color ? couldn't solve it.

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6 weeks ago, hide # |
 
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Is it normal to be able to do D but can't do C?

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6 weeks ago, hide # |
 
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Easy E,Hard F,Confusing D

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    6 weeks ago, hide # ^ |
     
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    Can you please briefly explain your approach for E ? I was stuck :(

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      6 weeks ago, hide # ^ |
      ← Rev. 2  
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      This is how I did it:

      Spoiler
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6 weeks ago, hide # |
 
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sort queries forces.

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6 weeks ago, hide # |
 
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由中国的吗？

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6 weeks ago, hide # |
 
Vote: I like it -9 Vote: I do not like it

First NEGATIVE delta

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6 weeks ago, hide # |
 
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Can someone explain how to solve D?

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6 weeks ago, hide # |
 
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how to solve F?

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    6 weeks ago, hide # ^ |
    ← Rev. 4  
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    Spoiler

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6 weeks ago, hide # |
 
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Can someone tell me why my solution for D is WA? Here's my code:

#include <bits/stdc++.h>
using namespace std;
#define int long long
char a[300010];
int b[300010],cnt[300010],n,q;
signed main(){
	ios::sync_with_stdio(0);
	cin.tie(0);
	cout.tie(0);
	cin>>n>>q;
	a[0]='a';
	for(int i=1;i<=q;i++){
		int op;
		cin>>op;
		a[i]=a[i-1];
		if(op==1){
			int x;
			cin>>x;
			cnt[x]++;
			if(cnt[x]%2==1) b[x]=i;
		}else{
			char c;
			cin>>c;
			a[i]=c;
		}
	}
	for(int i=1;i<=n;i++){
		if(cnt[i]%2==0) cout<<a[q];
		else cout<<a[b[i]];
	}
	
	return 0;
}
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5 weeks ago, hide # |
 
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Someone, if you solved F, please give me the approach, i have exhausted everything i had to solve that and couldn't progress a bit:(.

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