Day11 - 2D Arrays (Python 3)

• URL : https://www.hackerrank.com/challenges/30-2d-arrays/problem

• Objective
  • Today, we’re building on our knowledge of Arrays by adding another dimension. Check out the Tutorial tab for learning materials and an instructional video!
• Context

  • Given a 6 x 6 2D Array, A: [[1 1 1 0 0 0] [0 1 0 0 0 0] [1 1 1 0 0 0] [0 0 0 0 0 0] [0 0 0 0 0 0] [0 0 0 0 0 0]]

  • We define an hourglass in A to be a subset of values with indices falling in this pattern in A’s graphical representation:

    1 2 3

    a b c d e f g

  • There are 16 hourglasses in A, and an hourglass sum is the sum of an hourglass’ values.
• Task
  • Calculate the hourglass sum for every hourglass in A, then print the maximum hourglass sum.
• Input Format
  • There are 6 lines of input, where each line contains 6 space-separated integers describing 2D Array A; every value in A will be in the inclusive range of -9 to 9.
• Constraints
  • -9 <= A[i][j] <= 9
  • 0 <= i,j <= 5
• Output Format
  • Print the largest (maximum) hourglass sum found in A.

문제풀이

• 6 x 6의 배열에서 모든 3 x 3 배열의 합계 중 가장 큰 수를 출력
• 배열의 인덱스를 for문으로 주고 각 경우의 수를 다 더하여 리스트에 추가시킨 뒤 가장 큰수를 출력
• 2번째 행은 2번째 숫자만 더해야함

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import math
import os
import random
import re
import sys

if __name__ == '__main__':
    arr = []
    result = []
    for _ in range(6):
        arr.append(list(map(int, input().rstrip().split())))
    
    for i in range(4):
        for j in range(4):
            result.append(arr[i][j] + arr[i][j+1] + arr[i][j+2] + \
                                      arr[i+1][j+1]+ \
                          arr[i+2][j] + arr[i+2][j+1] + arr[i+2][j+2])
    print(max(result))

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arr = [[1, 1, 1, 0, 0, 0], 
       [0, 1, 0, 0, 0, 0], 
       [1, 1, 1, 0, 0, 0], 
       [0, 0, 2, 4, 4, 0], 
       [0, 0, 0, 2, 0, 0], 
       [0, 0, 1, 2, 4, 0]]

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# arr[0][0] ~ arr[2][2]
result = []
for i in range(4):
    for j in range(4):
        result.append(arr[i][j] + arr[i][j+1] + arr[i][j+2] + \
                      arr[i+1][j] + arr[i+1][j+1] + arr[i+1][j+2] + \
                      arr[i+2][j] + arr[i+2][j+1] + arr[i+2][j+2])
print(result)
print(max(result))

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[7, 5, 2, 0, 6, 9, 11, 8, 5, 10, 13, 10, 3, 11, 19, 16]
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