def word_to_num(word):
    d=
{'a':'2','b':'2','c':'2','d':'3','e':'3','f':'3','g':'4','h':'4','i':'1','j':'1','k':'5','l':'5','m':'6','n':'6','o':'0','p':'7','q':'0','r':'7','s':'7','t':'8','u':'8','v':'8','w':'9','x':'9','y':'9','z':'0'}
    s=''
    for i in word:
        s+=d[i]
    return s
from itertools import permutations
while True:
    num_dict={}
    num_list=[]
    word_list=[]
    num = input()
    if num=='-1':
        break
    loop_len = int(input())
    for i in range(loop_len):
        word_list.append(input())
    for item in word_list:
        num_dict[word_to_num(item)]=item
        num_list.append(word_to_num(item))
    perm = permutations(num_list,2)
    x=0
    for k,v in list(perm):
        if k+v==num:
            print(num_dict[k]+' '+num_dict[v])
        else:
            x += 1

    if x==loop_len*(loop_len-1):
        print('No solution')

Правда вне рейтинга:)

One way I can think of is to sort edge by cost
and use dynamic connectivity

But it's very hard to implement :(
What's the better solution?

O(n*sqrt(n)*log(n)) enough?

Upd: OK with this complexity. But 2.7 c++. How to solve with 0.1 second?

Edited by author 21.02.2026 00:26

Hey admins, I've sent a couple of tests to timus_support@acm.timus.ru that my AC solution was struggling with. Please validate if they can be added to the system.

Any way to remove test miners from the board?

Oleg Vasilenko (Chelyabinsk) - https://acm.timus.ru/status.aspx?space=1&num=1589&author=55499&from=10681678

Ruben Ashughyan - https://acm.timus.ru/status.aspx?space=1&num=1589&author=202317&from=10649282

kostan3 - https://acm.timus.ru/status.aspx?space=1&num=1589&author=121982 (looks suspicious, is it a system account or something?)

Can you give me some "extra" test or smth like that... My prog passed all my tests but i get wa#3...

Thnx!

Accepted:)

Edited by author 18.02.2026 21:32

тест 1: n=9 k=2
тест 2: n=1 k=1
тест 3: n=10 k=1
тест 4: n=8 k=1
тест 5: n=10 k=2
тест 6: n=7 k=2
тест 7: n=1 k=2
тест 8: n=2
тест 9: n=10 k=5
тест 10: n=9 k=5
n=3,4,5,6 не встречается...

incorrectly selected transfer

static void Main(string[] args)
{
   int n = int.Parse(Console.ReadLine());
   int[] values = new int[n];
   for (int i = 0; i < n + 1; i++)
      {
         string[] str = Console.ReadLine().Split();
         int a = int.Parse(str[0]) - 1;
         int b = int.Parse(str[1]) - 1;
         int c = int.Parse(str[2]);

         for (int j = a; j <= b; j++)
            {
               values[j] += c;
            }
      }

   Console.Write(string.Join(" ", values));
}


It's simple algorithm. How to speed it up? Which algorithm should I use?

Edited by author 21.01.2026 21:22

pls some test for W6

Hi, I writed this post because I wanted to share with you some of the test cases* that helped me a lot at the time. I hope it helps you :)

--> Test 1:

1
A B C

--> Answer:

A undefined
B undefined
C undefined

------------------------------

--> Test 2:

5
Isenbaev A B
A B C
D Q P
C H N
G N P

--> Answer:

A 1
B 1
C 2
D 5
G 4
H 3
Isenbaev 0
N 3
P 4
Q 5

------------------------------

--> Test 3:

13
Fominykh Isenbaev BBB
BBB CCC AAA
Ayzenshteyn Oparin Samsonov
Ayzenshteyn Chevdar Samsonov
Dublennykh Fominykh Ivankov
Burmistrov Dublennykh Kurpilyanskiy
Cormen Leiserson Rivest
Oparin AA AAA
Isenbaev Oparin Toropov
AA DD PP
PP QQ RR
RR SS TT
TT Toropov Oparin

--> Answer:

AA 2
AAA 2
Ayzenshteyn 2
BBB 1
Burmistrov 3
CCC 2
Chevdar 3
Cormen undefined
DD 3
Dublennykh 2
Fominykh 1
Isenbaev 0
Ivankov 2
Kurpilyanskiy 3
Leiserson undefined
Oparin 1
PP 3
QQ 4
RR 3
Rivest undefined
SS 3
Samsonov 2
TT 2
Toropov 1

------------------------------

--> Test 4:

3
Isenbaev A B
A B C
A Q W

--> Answer:

A 1
B 1
C 2
Isenbaev 0
Q 2
W 2

------------------------------

*(All test cases were made by other users, so you'll probably found them in other Posts/Topics/Discussions).

Acknowledgments to:
-> "Vit Demidenko" & "Nathalie"
-> "Pavel Nikolov"
-> "mccolt89"
-> "Megakrit"


-How I solved it:

I solved this problem in Java, for that, I used:

->1 java.util.Scanner
->1 java.util.HashMap
->1 java.util.TreeMap
->3 java.util.HashSet
->1 java.util.LinkedList
->? java.util.StringTokenizer (or you can just simply use the Scanner method "next()").

(The structures can be declared inside loops or other structures).

Hope all this helped you :)


Edited by author 08.04.2020 00:48

Edited by author 08.04.2020 00:49

See title I can currently solve problems under a rating of 50(I am a newbie) comfortably but I don't quite get how the difficulty scales really with some problems having a rating of 15000 which seems confusing. I just would like someone who has some knowledge to explain how difficulty scales numerically relative to some standard problems take codeforces or any major competitive programming competition as a reference

Edited by author 08.01.2026 08:49

min(P, 20)

The incorrect test 12 was fixed (coordinates were exceeding 10000).

New tests were added to the problem. The tests target a wide range of problems in geometry algorithms, accuracy issues, and performance.

All solutions have been rejudged. 229 authors (40%) lost, and 2 other authors gained the Solved status for the problem.

I'm expected brute force solution will accepted on C++, because N * 10^D integer divisions might work in 1 sec, but this solution work even on Python3.
Why is work? Is there a math prove that answer will be very small or in this problem weak tests?

Edited by author 14.02.2023 17:29

A bug was fixed in the checker program that incorrectly skipped most of the checks for some tests. The most affected tests are: 1, 3-8, 11, 17.

All solutions have been rejudged. The verdict changed for 40% of solutions (typical change patterns: WA5 -> WA4, WA9 -> WA7, AC -> WA11). 10 authors lost the Solved status for the problem.