As I sit admiring the rain (which I believe has come a bit too early in the year thanks to global warming), I am churning out code. I just love seeing functions. Each function performing an individual action and all of these interacting to achieve the objective of the program - I LOVE IT !!!
I wrote this script the day before MIT’s results were announced and due to a mistake committed by the admissions office ( 
) which had me in a bad mood for sometime, this script stayed underground.
The objective of this script was to solve question 22 of the Project Euler problem set ( the greatest set of problems ever ).
Here is the solution:
#Author: Shriphani Palakodety a.k.a PSP
import string
f = open("names.txt", "r")
names_list = f.read().split(‘","’)
names_list[0] = names_list[0][1:]
names_list[-1] = names_list[-1][0:6]
names_list.sort() #Arrange in alphabetical order.
def alphaDict():
alphadict = {}
alphastring = string.uppercase
for char in alphastring:
alphadict[char] = alphastring.find(char) + 1
return alphadict
def scorer(word):
”‘Make a score for each word’”
alphadict = alphaDict()
scores_list = []
for letter in word:
scores_list.append(alphadict[letter])
return sum(scores_list)
scores_list = []
for name in names_list:
scores_list.append((names_list.index(name) + 1) * scorer(name))
print sum(scores_list)
That particular solution took 0.83 seconds which I guess is ok considering what one of my brute force attempts on the collatz theorem took, 52 seconds. Well, I am happy with 0.83 seconds and I request and welcome everyone else to provide better solutions.
Well, here is the solution to question number 11 .
from operator import mulnumbers = ”‘\
08 02 22 97 38 15 00 40 00 75 04 05 07 78 52 12 50 77 91 08
49 49 99 40 17 81 18 57 60 87 17 40 98 43 69 48 04 56 62 00
81 49 31 73 55 79 14 29 93 71 40 67 53 88 30 03 49 13 36 65
52 70 95 23 04 60 11 42 69 24 68 56 01 32 56 71 37 02 36 91
22 31 16 71 51 67 63 89 41 92 36 54 22 40 40 28 66 33 13 80
24 47 32 60 99 03 45 02 44 75 33 53 78 36 84 20 35 17 12 50
32 98 81 28 64 23 67 10 26 38 40 67 59 54 70 66 18 38 64 70
67 26 20 68 02 62 12 20 95 63 94 39 63 08 40 91 66 49 94 21
24 55 58 05 66 73 99 26 97 17 78 78 96 83 14 88 34 89 63 72
21 36 23 09 75 00 76 44 20 45 35 14 00 61 33 97 34 31 33 95
78 17 53 28 22 75 31 67 15 94 03 80 04 62 16 14 09 53 56 92
16 39 05 42 96 35 31 47 55 58 88 24 00 17 54 24 36 29 85 57
86 56 00 48 35 71 89 07 05 44 44 37 44 60 21 58 51 54 17 58
19 80 81 68 05 94 47 69 28 73 92 13 86 52 17 77 04 89 55 40
04 52 08 83 97 35 99 16 07 97 57 32 16 26 26 79 33 27 98 66
88 36 68 87 57 62 20 72 03 46 33 67 46 55 12 32 63 93 53 69
04 42 16 73 38 25 39 11 24 94 72 18 08 46 29 32 40 62 76 36
20 69 36 41 72 30 23 88 34 62 99 69 82 67 59 85 74 04 36 16
20 73 35 29 78 31 90 01 74 31 49 71 48 86 81 16 23 57 05 54
01 70 54 71 83 51 54 69 16 92 33 48 61 43 52 01 89 19 67 48′”
def gridMaker(numbers):
grid = {}
index = 0
for numstring in numbers.splitlines():
bummer = [ int(char) for char in numstring.split() ]
grid[index] = bummer
index += 1
return grid
grid = gridMaker(numbers)
def horizontalProd(index, grid):
”‘The structural unit of this function is a list’”
prods_list = []
num_list = grid[index]
for num_index in range(0, len(num_list) - 3):
prods = reduce(mul, num_list[num_index:num_index+4])
prods_list.append(prods)
return max(prods_list)
def verticalProd(vertical_index, grid):
”‘The structural unit of this function is a vertical column i.e. dict[index][0]
for index between 0 and 20′”
prods_list = []
num_list = []
for index in range(0, 20):
num_list.append(grid[index][vertical_index])
for num_index in range(0, len(num_list) -3):
prods = reduce(mul, num_list[num_index:num_index+4])
prods_list.append(prods)
return max(prods_list)
def prepareMatrix(grid):
num_matrix = []
for i in range(0, 20):
num_matrix.append(grid[i])
return num_matrix
def diagonalProd(grid_key, grid_value, grid):
base_matrix = numpy.mat(prepareMatrix(grid))
sub_matrix = base_matrix[grid_key:grid_key+4, grid_value:grid_value+4]
return reduce(mul, numpy.diagonal(sub_matrix))
def prepareInvertMatrix(grid):
num_matrix = []
for i in range(0, 20):
num_list = grid[i]
num_list.reverse()
num_matrix.append(num_list)
return numpy.mat(num_matrix)
def inverseDiagonalProd(grid_key, grid_value, grid):
base_matrix = prepareInvertMatrix(grid)
sub_matrix = base_matrix[grid_key:grid_key+4, grid_value:grid_value+4]
return reduce(mul, numpy.diagonal(sub_matrix))
def maxHorProdList(grid):
prods_list = []
for i in range(0, 17):
prods_list.append(horizontalProd(i, grid))
return prods_list
def maxVerProdList(grid):
prods_list = []
for i in range(0, 17):
prods_list.append(verticalProd(i, grid))
return prods_list
def maxDiagProdList(grid):
prods_list = []
for i1 in range(0, 17):
for i2 in range(0, 17):
prods_list.append(diagonalProd(i1, i2, grid))
return prods_list
def maxInvertDiagProdList(grid):
prods_list = []
for i1 in range(0, 17):
for i2 in range(0, 17):
prods_list.append(inverseDiagonalProd(i1, i2, grid))
return prods_list
print max[maxHorProdList(grid) + maxVerProdList(grid) + maxDiagProdList(grid) + maxInvertDiagProdList(grid)]
This solution is “big” and I know it. But I wanted to get a basic hang of numpy and found that this sum would be an excellent opportunity to do so. Well, happy coding 
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