Array Manipulation in Python - HackerRank Solution

Solution for hackerRank problem Array Manipulation in Python

Problem :

Starting with a 1-indexed array of zeros and a list of operations, for each operation add a value to each the array element between two given indices, inclusive. Once all operations have been performed, return the maximum value in the array.

Example,

n = 10

queries = [ [1, 5, 3], [4, 8, 7], [6, 9, 1] ]

Queries are interpreted as follows:

Add the values of k between the indices a and b inclusive:

The largest value is 10 after all operations are performed.

Function Description

Complete the function arrayManipulation in the editor below.

arrayManipulation has the following parameters:

• int n - the number of elements in the array
• int queries[q][3] - a two dimensional array of queries where each queries[i] contains three integers, a, b, and k.

Returns

• int - the maximum value in the resultant array

Input Format

The first line contains two space-separated integers  n and  m, the size of the array and the number of operations.

Each of the next  m lines contains three space-separated integers a, b  and  k, the left index, right index and summand.

Constraints

• 3 <= n <= 10^7
• 1 <= m <= 2 * 10^5
• 1 <= a <=b <= n
• 0 <= k <=10^9

Sample Input

5  3

1  2  100

2  5  100

3  4  100

Sample Output

200

Explanation

After the first update the list is 100 100 0 0 0.

After the second update list is 100 200 100 100 100.

After the third update list is 100 200 200 200 100.

The maximum value is 200.

Code :

#!/bin/python3

import math

import os

import random

import re

import sys

#

# Complete the 'arrayManipulation' function below.

#

# The function is expected to return a LONG_INTEGER.

# The function accepts following parameters:

#  1. INTEGER n

#  2. 2D_INTEGER_ARRAY queries

#

def arrayManipulation(n, queries):

    l = [0 for i in range(n+1)]

    max_val=0

    sum_val=0

    for i in range(len(queries)):

        start=queries[i][0]

        end=queries[i][1]

        value=queries[i][2]

        l[start-1]+=value

        l[end]-=value

    for i in range(len(l)-1):

        sum_val=sum_val+l[i]

        if(sum_val>max_val):

            max_val=sum_val

    return max_val

        

if __name__ == '__main__':

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

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

    n = int(first_multiple_input[0])

    m = int(first_multiple_input[1])

    queries = []

    for _ in range(m):

        queries.append(list(map(int, input().rstrip().split())))

    result = arrayManipulation(n, queries)

    fptr.write(str(result) + '\n')

    fptr.close()