Python脚本09 —— 一个计算题

#coding=utf-8
# a + b - 9 = 4
# +   -   -
# c - d * e = 4
# /   *   -
# f + g - h = 4
# =   =   =
# 4   4   4

maxNumber = 20
minNumber = 0
for a in xrange(0,13):
b = 13 - a # 横着第一个公式得到 a + b = 13
for c in xrange(minNumber,maxNumber):
for d in xrange(minNumber,maxNumber):
for e in xrange(0,5):
for f in xrange(1,maxNumber):# 竖着第一个公式有除法，所以f不能为0. 且为了避免int作除法结果被截断，增加默认公式c == f * (4 - a)
for g in xrange(minNumber,maxNumber):
h = 5 - e #竖着最后一个公式得到 e + h = 5
if (a + b - 9 == 4) and (c - d * e == 4) and (f + g - h == 4) and (a + c / f == 4) and (c == f * (4 - a)) and (b - d * g == 4) and (9 - e - h == 4):
print str(a) + ' + ' + str(b) + ' - 9 = 4'
print '+   -   -'
print str(c) + ' - ' + str(d) + ' * ' + str(e) + ' = 4'
print '/   *   -'
print str(f) + ' + ' + str(g) + ' - ' + str(h) + ' = 4'
print '=   =   ='
print '4   4   4'