ken_love_rin's blog

By ken_love_rin, history, 9 years ago, In English

Give an integer N (N<=5000). How many different premutations of sequence 1..n (p[1],p[2]...p[n]) so that p[i]<>i with 1<=i<=n. It means the i-th number in a permutation must be different with its index.

for example

input 2 output 1 (2,1)

input 3 output 2 {(2,3,1); (3,1,2)}

input 4 output 9

Can you give me a solution. thank you very much and sorry about my bad english. :)

Full text and comments »

  • Vote: I like it
  • -8
  • Vote: I do not like it

By ken_love_rin, history, 9 years ago, In English

Help me. thanks.

Give a sequence of numbers a1,a2...an. (n<=2*10^5, 0<a[i]<=10^6). Find the maximum of (a[i] mod a[j]) a[i]>=a[j], (1<=i,j<=n).

For example

input

3 2 4 5

output 1 ( 5 mod 4)

intput

3 15 22 44

output

14 ( 44 mod 15 ).

Full text and comments »

  • Vote: I like it
  • 0
  • Vote: I do not like it

By ken_love_rin, history, 9 years ago, In English

Hi CF. help me please :)

problems at COCI2015. TASK ACM

The team of the University of Zagreb – Stjepan, Ivan and Gustav – are taking part in the World Finals of the ACM International Collegiate Programming Contest in Morocco. Their technical guide Goran has come up with an invincible strategy to use for solving tasks in the finals. In the very beginning, each team member quickly estimates the difficulty of each of the N tasks. The difficulties are described by numbers from 1 to 5, and their meaning is the following:

• 1 hehehe • 2 bring it on! • 3 well OK. • 4 hmmmm. . . • 5 are you insane?

After this, they will distribute the tasks between them. For simplicity’s sake, the array of tasks will be split into three parts so that each team member gets a nonempty array of consecutive tasks to contemplate about. The distribution is made so that the sum of estimated difficulties is minimal, whereas only the estimate of the team member whom that task is assigned to is calculated. Your task is to calculate that minimal possible sum.

INPUT

The first line of input contains the integer N (3 6 N 6 150 000), the number of tasks. Each of the following three lines contains N integers (from 1 to 5): the estimated task difficulties, given respectively. First of those lines corresponds to Stjepan’s estimates, the second to Ivan’s and the third to Gustav’s.

OUTPUT

The first and only line of output must contain the minimal sum of difficulties.

SAMPLE TESTS

input

3

1 3 3

1 1 1

1 2 3

output 4

input

7

3 3 4 1 3 4 4

4 2 5 1 5 5 4

5 5 1 3 4 4 4

output 19

Clarification of the first example: Stjepan gets the first, Gustav the second, and Ivan the third task.

Full text and comments »

  • Vote: I like it
  • 0
  • Vote: I do not like it

By ken_love_rin, history, 9 years ago, In English

can you help me?

You are given an array of N integers. Find a consecutive subsequence of numbers of the length at least K that has the maximal possible average. Please note: the average of a subsequence is the sum of all the numbers in the subsequence divided by its length. INPUT The first line of input contains two integers N (1 6 N 63 · 105) and K (16 K 6 N). The second line of input contains N integers ai (16 ai 6106). OUTPUT The first and only line of output must contain the maximal possible average. An absolute deviation of ±0.001 from the official solution is permitted. SCORING In test cases worth 30% of total points, it will hold that N is not larger than 5000. SAMPLE TESTS

input
  6 3 
  7 1 2 1 3 6
  output
  3.333333

Full text and comments »

  • Vote: I like it
  • +3
  • Vote: I do not like it

By ken_love_rin, 9 years ago, In English

i am try my best!!!

Full text and comments »

  • Vote: I like it
  • -17
  • Vote: I do not like it