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@joostrijneveld
Last active August 29, 2015 14:06
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Computes if/when it makes sense for the defending player in Risk to choose to throw only one die (if allowed).
#! /usr/bin/env python
def printmatrix(matrix):
""" source:
http://stackoverflow.com/questions/13214809/pretty-print-2d-python-list """
s = [[str(e) for e in row] for row in [['['+str(n)+']' for n in range(1, 7)]]+matrix]
lens = [len(max(col, key=len)) for col in zip(*s)]
fmt = '\t'.join('{{:{}}}'.format(x) for x in lens)
table = ['['+str(n)+"]\t"+fmt.format(*row) for (row, n) in zip(s, range(0, len(s)+1))]
table[0] = ' '+table[0][3:] # to remove the [0]
print('\n'.join(table))
one = [[0]*6 for x in range(6)] # (w, l) are the chances of wining / losing 1
two = [[0]*6 for x in range(6)] # (w, d, l) are the chances of winning 2 / 1v1 / losing 2
exp = [[0]*6 for x in range(6)] # (e1, e2) are the expected values throwing 1 or 2 dice respectively
choice = [[0]*6 for x in range(6)] # best choice based on expected value
for a in range(0, 6):
for b in range(0, 6):
if (a < b):
a, b = b, a
one[a][b] = ((6-a)/6.0, 1 - (6-a)/6.0)
two[a][b] = [0, 0, 0]
for c in range(1, 7):
for d in range(1, 7):
if c < d:
c, d = d, c
if c >= a + 1:
if d >= b + 1:
two[a][b][0] += 1
else:
two[a][b][1] += 1
else:
if d >= b + 1:
two[a][b][1] += 1
else:
two[a][b][2] += 1
two[a][b] = tuple([x/36.0 for x in two[a][b]])
exp[a][b] = (one[a][b][0] - one[a][b][1], 2*two[a][b][0] - 2*two[a][b][2])
choice[a][b] = '1' if exp[a][b][0] > exp[a][b][1] else '2'
for a in range(1, 6):
for b in range(0, a):
one[b][a] = one[a][b]
two[b][a] = two[a][b]
exp[b][a] = exp[a][b]
choice[b][a] = choice[a][b]
for a in range(0, 6):
for b in range(0, 6):
one[a][b] = "{0:.2f} {1:.2f}".format(*one[a][b])
two[a][b] = "{0:.2f} {1:.2f} {2:.2f}".format(*two[a][b])
exp[a][b] = "{0:.2f} {1:.2f}".format(*exp[a][b])
print(">>>> One die (w/l):")
printmatrix(one)
print(">>>> Two dice (w2/1v1/l2):")
printmatrix(two)
print(">>>> Expected values (1 die, 2 dice):")
printmatrix(exp)
print(">>>> Best choice:")
printmatrix(choice)
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