Lisa's Workbook

 Lisa just got a new math workbook. A workbook contains exercise problems, grouped into chapters. Lisa believes a problem to be special if its index (within a chapter) is the same as the page number where it's located. The format of Lisa's book is as follows:

• There are  chapters in Lisa's workbook, numbered from  to .
• The  chapter has  problems, numbered from  to .
• Each page can hold up to  problems. Only a chapter's last page of exercises may contain fewer than  problems.
• Each new chapter starts on a new page, so a page will never contain problems from more than one chapter.
• The page number indexing starts at .

Given the details for Lisa's workbook, can you count its number of special problems?

Example

Lisa's workbook contains  problems for chapter , and  problems for chapter . Each page can hold  problems.

The first page will hold  problems for chapter . Problem  is on page , so it is special. Page  contains only Chapter , Problem , so no special problem is on page . Chapter  problems start on page  and there are  problems. Since there is no problem  on page , there is no special problem on that page either. There is  special problem in her workbook.

Note: See the diagram in the Explanation section for more details.

Function Description

Complete the workbook function in the editor below.

workbook has the following parameter(s):

• int n: the number of chapters
• int k: the maximum number of problems per page
• int arr[n]: the number of problems in each chapter

Returns
- int: the number of special problems in the workbook

Input Format

The first line contains two integers  and , the number of chapters and the maximum number of problems per page.
The second line contains  space-separated integers  where  denotes the number of problems in the  chapter.

Constraints

Sample Input

STDIN       Function
-----       --------
5 3         n = 5, k = 3
4 2 6 1 10  arr = [4, 2, 6, 1, 10]

Sample Output

4

Explanation

The diagram below depicts Lisa's workbook with  chapters and a maximum of  problems per page. Special problems are outlined in red, and page numbers are in yellow squares.

There are  special problems and thus we print the number  on a new line.

#!/bin/python3

import math

import os

import random

import re

import sys

#

# Complete the 'workbook' function below.

#

# The function is expected to return an INTEGER.

# The function accepts following parameters:

#  1. INTEGER n

#  2. INTEGER k

#  3. INTEGER_ARRAY arr

#

def workbook(n, k, arr):

    page=0

    sp_prob=0

    # Write your code here

    for i in range(0,n):

        prob=0

        page+=1

        for j in range(0,arr[i]):

            prob+=1

    

            if prob==page:

                sp_prob+=1

                

            if prob%k==0 and j!=arr[i]-1:

                page+=1

                

    return sp_prob

            

if __name__ == '__main__':

    fptr = open(os.environ['OUTPUT_PATH'], 'w')

    first_multiple_input = input().rstrip().split()

    n = int(first_multiple_input[0])

    k = int(first_multiple_input[1])

    arr = list(map(int, input().rstrip().split()))

    result = workbook(n, k, arr)

    fptr.write(str(result) + '\n')

    fptr.close()

Compiler Message

Success

Input (stdin)

• 10 5

• 3 8 15 11 14 1 9 2 24 31

Expected Output

• 8