Exploring Python with Euler

By Mat Kelly

At the advice of some other programmers and my desire to learn python, I have taken it onto myself to trudge through the problems at Project Euler as time permits. Being completely unfamiliar with Python's syntax and data structures, I figured doing so would allow me to get comfortable with writing basic programs using only the language's primatives.

The first few were not very difficult once I got the hang of the looping structures, but Problem 11 served as a true test in my understanding of the range concept in specifying bounds for a loop. After quickly whipping up this solution and cross-referencing with the forum I realized a few concepts that would more efficiently do what I did in a much shorter fashion.

#Project Euler
# problem 11

l  = "08 02 22 97 38 15 00 40 00 75 04 05 07 78 52 12 50 77 91 08 "
l += "49 49 99 40 17 81 18 57 60 87 17 40 98 43 69 48 04 56 62 00 "
l += "81 49 31 73 55 79 14 29 93 71 40 67 53 88 30 03 49 13 36 65 "
l += "52 70 95 23 04 60 11 42 69 24 68 56 01 32 56 71 37 02 36 91 "
l += "22 31 16 71 51 67 63 89 41 92 36 54 22 40 40 28 66 33 13 80 "
l += "24 47 32 60 99 03 45 02 44 75 33 53 78 36 84 20 35 17 12 50 "
l += "32 98 81 28 64 23 67 10 26 38 40 67 59 54 70 66 18 38 64 70 "
l += "67 26 20 68 02 62 12 20 95 63 94 39 63 08 40 91 66 49 94 21 "
l += "24 55 58 05 66 73 99 26 97 17 78 78 96 83 14 88 34 89 63 72 "
l += "21 36 23 09 75 00 76 44 20 45 35 14 00 61 33 97 34 31 33 95 "
l += "78 17 53 28 22 75 31 67 15 94 03 80 04 62 16 14 09 53 56 92 "
l += "16 39 05 42 96 35 31 47 55 58 88 24 00 17 54 24 36 29 85 57 "
l += "86 56 00 48 35 71 89 07 05 44 44 37 44 60 21 58 51 54 17 58 "
l += "19 80 81 68 05 94 47 69 28 73 92 13 86 52 17 77 04 89 55 40 "
l += "04 52 08 83 97 35 99 16 07 97 57 32 16 26 26 79 33 27 98 66 "
l += "88 36 68 87 57 62 20 72 03 46 33 67 46 55 12 32 63 93 53 69 "
l += "04 42 16 73 38 25 39 11 24 94 72 18 08 46 29 32 40 62 76 36 "
l += "20 69 36 41 72 30 23 88 34 62 99 69 82 67 59 85 74 04 36 16 "
l += "20 73 35 29 78 31 90 01 74 31 49 71 48 86 81 16 23 57 05 54 "
l += "01 70 54 71 83 51 54 69 16 92 33 48 61 43 52 01 89 19 67 48"

x = l.split(" ")

largestProduct = 0

#Project Euler
# problem 11

##
#LEFT TO RIGHT
##
for row in range (0,20):
 for col in range(0,17):
  product = 1
  for i in range(0,4):
   product*= int(x[(20*row)+col+i]) 
  
  if product>largestProduct:
   largestProduct = product

###
#TOP TO BOTTOM
###

for row in range (0,17):
 for col in range(0,20):
  product = 1
  for i in range(0,4):
   product*= int(x[(20*row)+(20*i)+col]) 
  
  if product>largestProduct:
   largestProduct = product

###
#DIAG LEFT
###

for row in range (0,17):
 for col in range(0,17):
  product = 1
  for i in range(0,4):
   product*= int(x[(20*row)+(i*20)+i+col]) 
   
  if product>largestProduct:
   largestProduct = product

###
#DIAG LEFT
###

for row in range (0,17):
 for col in range(3,20):
  product = 1
  for i in range(0,4):
   product*= int(x[(20*row)+(i*20)+col-i]) 
     
  if product>largestProduct:
   largestProduct = product

print largestProduct