Project Euler 11: (Iron)Python
- by Ben Griswold
In my attempt to learn (Iron)Python out in the open, here’s my solution for Project Euler Problem 11.
As always, any feedback is welcome.
# Euler 11
# http://projecteuler.net/index.php?section=problems&id=11
# What is the greatest product
# of four adjacent numbers in any direction (up, down, left,
# right, or diagonally) in the 20 x 20 grid?
import time
start = time.time()
grid = [\
[8,02,22,97,38,15,00,40,00,75,04,05,07,78,52,12,50,77,91,8],\
[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],\
[67,26,20,68,02,62,12,20,95,63,94,39,63,8,40,91,66,49,94,21],\
[24,55,58,05,66,73,99,26,97,17,78,78,96,83,14,88,34,89,63,72],\
[21,36,23,9,75,00,76,44,20,45,35,14,00,61,33,97,34,31,33,95],\
[78,17,53,28,22,75,31,67,15,94,03,80,04,62,16,14,9,53,56,92],\
[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],\
[04,52,8,83,97,35,99,16,07,97,57,32,16,26,26,79,33,27,98,66],\
[88,36,68,87,57,62,20,72,03,46,33,67,46,55,12,32,63,93,53,69],\
[04,42,16,73,38,25,39,11,24,94,72,18,8,46,29,32,40,62,76,36],\
[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]]
# left and right
max, product = 0, 0
for x in range(0,17):
for y in xrange(0,20):
product = grid[y][x] * grid[y][x+1] * \
grid[y][x+2] * grid[y][x+3]
if product > max : max = product
# up and down
for x in range(0,20):
for y in xrange(0,17):
product = grid[y][x] * grid[y+1][x] * \
grid[y+2][x] * grid[y+3][x]
if product > max : max = product
# diagonal right
for x in range(0,17):
for y in xrange(0,17):
product = grid[y][x] * grid[y+1][x+1] * \
grid[y+2][x+2] * grid[y+3][x+3]
if product > max: max = product
# diagonal left
for x in range(0,17):
for y in xrange(0,17):
product = grid[y][x+3] * grid[y+1][x+2] * \
grid[y+2][x+1] * grid[y+3][x]
if product > max : max = product
print max
print "Elapsed Time:", (time.time() - start) * 1000, "millisecs"
a=raw_input('Press return to continue')
